Update MAP_TYPE value for hppa from Linux 4.17.

This patch updates the hppa definition of MAP_TYPE to reflect a
corresponding change in the Linux kernel in 4.17 (so the value now has
four bits set, as it does on other architectures, although they are
different from other architectures because of hppa differences in
other MAP_* bits).

Tested with build-many-glibcs.py for hppa.

	* sysdeps/unix/sysv/linux/hppa/bits/mman.h [__USE_MISC]
	(MAP_TYPE): Change value to 0x2b.