intel: Fixes for mesa to compile on FreeBSD
- PAGE_SIZE defined in various files is already defined in machine/param.h so #ifndef had been used.
- Static struct bitset was renamed to brw_bitset as a struct bitset is defined in sys/_bitset.h included by pthread_np.h on FreeBSD.
- On Linux ENODATA is defined but on BSD, and MacOSX ENOATTR is used instead. Defined ENODATA to be ENOATTR when the system is not Linux.
Signed-off-by: Eleni Maria Stea firstname.lastname@example.org