MIPS: Testsuite fixes for soft-float configurations

MIPS: Testsuite fixes for soft-float configurations

gcc/testuite/

	* gcc.target/mips/mips.exp: Add support for -msoft-float
	and -mhard-float options.  Ensure that explicit -mfp*
	options imply both -mhard-float and -mdouble-float.
	* gcc.target/mips/call-clobbered-1.c: Add -mhard-float to the
	compile options.

From-SVN: r218047