F-9724: partial-flash-write uses bitwise NOT

The formula is data | ~current_data (bitwise); the comment used the
logical '!'

hal/pic32c.c

@@ -223,7 +223,7 @@ int pic32_flash_write(uint32_t address, const uint8_t *data, int len)
             _addr = pic32_addr_dqword_align(address);
             /* Setup an aligned buffer with the following rules:
              * - For addresses outside the writing range: 0xFF (no change)
-             * - For addresses inside the writing range: data | !current_data
+             * - For addresses inside the writing range: data | ~current_data
              *
              * This approach ensures we only flip bits from 1 to 0 when writing
              * without an erase operation. When the address is aligned and length