t-rs6000: Move contents to t-fprules...

t-rs6000: Move contents to t-fprules...

	* config/rs6000/t-rs6000: Move contents to t-fprules,
	add rules for dependencies of rs6000.o and to build rs6000-c.o
	* config/rs6000/t-fprules: New file from t-rs6000.
	* config/rs6000/t-beos: Remove soft-fp rules.
	* config/rs6000/t-ppccomm: Likewise.
	* config/rs6000/t-newas: Likewise.
	* config/rs6000/t-rs6000-c-rule: Delete.
	* config.gcc: Use t-fprules for rs6000/ ports when appropriate.
	Use t-rs6000 for all rs6000/ ports instead of t-rs6000-c-rule.
	Create generic Darwin rules.

From-SVN: r60265