Remove unreachable code

IAR generates warning Pe111 'statement is unreachable'. GCC doesn't
complain about their absence, if they are removed.

adc/microphone_adc/microphone_adc.c

@@ -44,6 +44,4 @@ int main() {
         printf("%.2f\n", adc_raw * ADC_CONVERT);
         sleep_ms(10);
     }
-
-    return 0;
 }

adc/onboard_temperature/onboard_temperature.c

@@ -58,6 +58,4 @@ int main() {
 #endif
         sleep_ms(990);
     }
-
-    return 0;
 }

gpio/hello_7segment/hello_7segment.c

@@ -89,7 +89,5 @@ int main() {
         sleep_ms(250);
         gpio_clr_mask(mask);
     }
-
-    return 0;
 }
 /// \end::hello_gpio[]

gpio/hello_gpio_irq/hello_gpio_irq.c

@@ -27,8 +27,6 @@ int main() {
 
     // Wait forever
     while (1);
-
-    return 0;
 }
 
 

hello_world/serial/hello_serial.c

@@ -13,5 +13,4 @@ int main() {
         printf("Hello, world!\n");
         sleep_ms(1000);
     }
-    return 0;
 }

hello_world/usb/hello_usb.c

@@ -13,5 +13,4 @@ int main() {
         printf("Hello, world!\n");
         sleep_ms(1000);
     }
-    return 0;
 }

i2c/bmp280_i2c/bmp280_i2c.c

@@ -214,6 +214,7 @@ int main() {
 #if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
     #warning i2c / bmp280_i2c example requires a board with I2C pins
         puts("Default I2C pins were not defined");
+    return 0;
 #else
     // useful information for picotool
     bi_decl(bi_2pins_with_func(PICO_DEFAULT_I2C_SDA_PIN, PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C));
@@ -248,7 +249,5 @@ int main() {
         // poll every 500ms
         sleep_ms(500);
     }
-
 #endif
-    return 0;
 }

i2c/lcd_1602_i2c/lcd_1602_i2c.c

@@ -163,7 +163,5 @@ int main() {
             lcd_clear();
         }
     }
-
-    return 0;
 #endif
 }

i2c/lis3dh_i2c/lis3dh_i2c.c

@@ -125,5 +125,4 @@ int main() {
         printf("\e[1;1H\e[2J");
     }
 #endif
-    return 0;
 }

i2c/mpl3115a2_i2c/mpl3115a2_i2c.c

@@ -162,6 +162,7 @@ int main() {
 #if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
 #warning i2c / mpl3115a2_i2c example requires a board with I2C pins
     puts("Default I2C pins were not defined");
+    return 0;
 #else
     printf("Hello, MPL3115A2. Waiting for something to interrupt me!...\n");
 
@@ -202,5 +203,4 @@ int main() {
     };
 
 #endif
-    return 0;
 }

i2c/mpu6050_i2c/mpu6050_i2c.c

@@ -82,6 +82,7 @@ int main() {
 #if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
     #warning i2c/mpu6050_i2c example requires a board with I2C pins
     puts("Default I2C pins were not defined");
+    return 0;
 #else
     printf("Hello, MPU6050! Reading raw data from registers...\n");
 
@@ -111,7 +112,5 @@ int main() {
 
         sleep_ms(100);
     }
-
 #endif
-    return 0;
 }

i2c/pa1010d_i2c/pa1010d_i2c.c

@@ -152,5 +152,4 @@ int main() {
         printf("\e[1;1H\e[2J");
     }
 #endif
-    return 0;
 }

i2c/pcf8523_i2c/pcf8523_i2c.c

@@ -159,6 +159,5 @@ int main() {
         printf("\e[1;1H\e[2J");
     }
 #endif
-    return 0;
 }
 

rtc/hello_rtc/hello_rtc.c

@@ -43,7 +43,5 @@ int main() {
         printf("\r%s      ", datetime_str);
         sleep_ms(100);
     }
-
-    return 0;
 }
 /// \end::hello_rtc_main[]

rtc/rtc_alarm_repeat/rtc_alarm_repeat.c

@@ -56,6 +56,4 @@ int main() {
 
     // Alarm will keep firing forever
     while(1);
-
-    return 0;
 }

spi/bme280_spi/bme280_spi.c

@@ -235,7 +235,5 @@ int main() {
 
         sleep_ms(1000);
     }
-
-    return 0;
 #endif
 }

spi/max7219_32x8_spi/max7219_32x8_spi.c

@@ -135,7 +135,5 @@ int main() {
 
         bright++;
     }
-
-    return 0;
 #endif
 }

spi/max7219_8x7seg_spi/max7219_8x7seg_spi.c

@@ -142,7 +142,5 @@ int main() {
             j = 0;
         }
     }
-
-    return 0;
 #endif
 }

spi/mpu9250_spi/mpu9250_spi.c

@@ -150,6 +150,4 @@ int main() {
 
         sleep_ms(100);
     }
-
-    return 0;
 }

usb/device/dev_hid_composite/main.c

@@ -65,8 +65,6 @@ int main(void)
 
     hid_task();
   }
-
-  return 0;
 }
 
 //--------------------------------------------------------------------+

usb/device/dev_lowlevel/dev_lowlevel.c

@@ -575,6 +575,4 @@ int main(void) {
     while (1) {
         tight_loop_contents();
     }
-
-    return 0;
 }

usb/host/host_cdc_msc_hid/main.c

@@ -61,8 +61,6 @@ int main(void)
     hid_app_task();
 #endif
   }
-
-  return 0;
 }
 
 //--------------------------------------------------------------------+