firmware-utils: motorola-bin: fix compiler warnings/errors
motorola-bin.c:146:11: error: comparison of integer expressions of different signedness: ‘off_t’ {aka ‘long int’} and ‘long unsigned int’ [-Werror=sign-compare]
motorola-bin.c:173:79: error: comparison of integer expressions of different signedness: ‘ssize_t’ {aka ‘long int’} and ‘long unsigned int’ [-Werror=sign-compare]
motorola-bin.c:214:57: error: comparison of integer expressions of different signedness: ‘ssize_t’ {aka ‘long int’} and ‘long unsigned int’ [-Werror=sign-compare]
Signed-off-by: Petr Štetiar <ynezz@true.cz>