lex.c (search_line_fast): Add new version to be used for Power8 and later targets when Altivec is enabled.

2014-10-03  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	* lex.c (search_line_fast): Add new version to be used for Power8
	and later targets when Altivec is enabled.  Restrict the existing
	Altivec version to big-endian systems so that lvsr is not used on
	little endian, where it is deprecated.  Remove LE-specific code
	from the now-BE-only version.

From-SVN: r215873