[binutils-gdb] Remove regcache_raw_write_part

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 4f0420fdabda76f462bd29a02d9be575e0e0cce7 ***

Author: Simon Marchi <simon.marchi@ericsson.com>
Branch: master
Commit: 4f0420fdabda76f462bd29a02d9be575e0e0cce7

Remove regcache_raw_write_part

Remove regcache_raw_write_part, update callers to use
regcache::raw_write_part instead.

gdb/ChangeLog:

	* regcache.h (regcache_raw_write_part): Remove, update callers
	to use regcache::raw_write_part instead.
	* regcache.c (regcache_raw_write_part): Remove.