Prefer INT_SSE_REGS for SSE_FLOAT_MODE_P in preferred_reload_class.

When moves between integer and sse registers are cheap.

2021-12-06  Hongtao Liu  <Hongtao.liu@intel.com>
	    Uroš Bizjak  <ubizjak@gmail.com>
gcc/ChangeLog:

	PR target/95740
	* config/i386/i386.c (ix86_preferred_reload_class): Allow
	integer regs when moves between register units are cheap.
	* config/i386/i386.h (INT_SSE_CLASS_P): New.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/pr95740.c: New test.