rs6000.c (rs6000_reg_live_or_pic_offset_p): Check TARGET_SINGLE_PIC_BASE for RS6000_PIC_OFFSET_TABLE_REGNUM.

	* config/rs6000/rs6000.c (rs6000_reg_live_or_pic_offset_p): Check
	TARGET_SINGLE_PIC_BASE for RS6000_PIC_OFFSET_TABLE_REGNUM.
	(rs6000_emit_prologue): Don't set PIC register if
	TARGET_SINGLE_PIC_BASE.
	* config/rs6000/rs6000.opt (msingle-pic-base): New option.
	* doc/invoke.texi (msingle-pic-base): Document.

From-SVN: r167283