[binutils-gdb] Remove const_char_ptr typedef

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 4f7deebe0c56863f0c97edfe9ac9931dfdfc8f0a ***

Author: Tom Tromey <tom@tromey.com>
Branch: master
Commit: 4f7deebe0c56863f0c97edfe9ac9931dfdfc8f0a

Remove const_char_ptr typedef

The const_char_ptr is no longer used, so it can be removed.

ChangeLog
2018-05-29  Tom Tromey  <tom@tromey.com>

	* objc-lang.h: Don't include cp-support.h.
	* common/gdb_vecs.h (const_char_ptr): Remove typedef.  Don't
	declare VEC.