Replace the remaining uses of strerror with safe_strerror

Replace the remaining uses of strerror with safe_strerror

To do that, this patch makes IPA compile safe-strerror as well. Because
it doesn't use Gnulib, it calls the Glibc version of strerror_r directly.

Consequently this patch also removes the configure checks for strerror.

gdb/ChangeLog:

2019-12-10  Christian Biesinger  <cbiesinger@google.com>

	* config.in: Regenerate.
	* configure: Regenerate.
	* gdbsupport/agent.c (gdb_connect_sync_socket): Call
	safe_strerror instead of strerror.
	* gdbsupport/common.m4: Don't check for strerror.
	* gdbsupport/safe-strerror.c: Support both the glibc version
	of strerror_r and the XSI version.

gdb/gdbserver/ChangeLog:

2019-12-10  Christian Biesinger  <cbiesinger@google.com>

	* Makefile.in: Add safe-strerror.c to gdbreplay and IPA, and change
	UNDO_GNULIB_CFLAGS to undo strerror_r instead of strerror.
	* config.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Don't check for strerror.
	* linux-i386-ipa.c (initialize_fast_tracepoint_trampoline_buffer):
	Call safe_strerror instead of strerror.
	* server.h (strerror): Remove this now-unnecessary declaration.
	* tracepoint.c (init_named_socket): Call safe_strerror instead of
	strerror.
	(gdb_agent_helper_thread): Likewise.
	* utils.c (perror_with_name): Likewise.

Change-Id: I74848f072dcde75cb55c435ef9398dc8f958cd73