Delete !HAVE_LD_PIE variants of startfile/endfile specs

Delete !HAVE_LD_PIE variants of startfile/endfile specs

The HAVE_LD_PIE variant doesn't contain anything that will break
linking when !HAVE_LD_PIE that isn't already broken if you choose to
build PIEs with a linker that doesn't support PIE.  All this
HAVE_LD_PIE protects is the choice of different crt files, which is
more about libc capability than linker capability.

	* config/gnu-user.h (GNU_USER_TARGET_STARTFILE_SPEC): Delete
	!HAVE_LD_PIE variant.
	(GNU_USER_TARGET_ENDFILE_SPEC): Likewise.

From-SVN: r266249