[binutils-gdb] Remove regcache_cooked_write

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT b66f5587de2a096f357124b20376b2bab980238b ***

Author: Simon Marchi <simon.marchi@ericsson.com>
Branch: master
Commit: b66f5587de2a096f357124b20376b2bab980238b

Remove regcache_cooked_write

Remove regcache_cooked_write, update callers to use
regcache::cooked_write.

gdb/ChangeLog:

	* regcache.h (regcache_cooked_write): Remove, update callers to
	use regcache::cooked_write.
	* regcache.c (regcache_cooked_write): Remove.