The definition of BOOL is different between macOS and iOS. C's
bool is used on iOS, but C's bool is hard to use from Go (e.g.,
an integer cannot be converted to C's bool). Use unsigned char
instead.
Fixes#1006
This change adds #ifs to enable to compile the driver on iOS.
This also removes BOOL, which can be a duplicated definition.
C's _Bool does not work well with Cgo. Use uint8_t instead for
boolean values.
