Allow functions for AVX target inline functions for lower target.  This bug was
reported here: http://gcc.gnu.org/ml/gcc-patches/2013-06/msg01620.html

2013-07-02  Sriraman Tallam  <tmsriram@google.com>

	* config/i386/i386.c (gate_insert_vzeroupper): Check if target
	ISA is AVX.
	(ix86_option_override_internal):Turn on all -mavx target flags by
	default as they are dependent on AVX anyway.

	* gcc.target/i386/avx-inline.c: New test.

From-SVN: r200627