Update img_to_array.py (raspberrypi#501)

when the last part of the image generate  in .h file it does not involve ";" at the end ,and will make error  when we start make the project

Author: wahidshirdel

i2c/ssd1306_i2c/img_to_array.py

@@ -73,7 +73,7 @@
         buffer.append(f'{out_byte:#04x}')
 
 buffer = ", ".join(buffer)
-buffer_hex = f'static uint8_t {img_name}[] = {{{buffer}}}\n'
+buffer_hex = f'static uint8_t {img_name}[] = {{{buffer}}};\n'
 
 with open(f'{img_name}.h', 'wt') as file:
     file.write(f'#define IMG_WIDTH {img_width}\n')