* config.gcc (rx-*-linux*): New target.
	* config/rx/elf.opt: New file.
	* config/rx/linux.h: Likewise.
	* config/rx/t-linux: Likewise.
	* config/rx/rx.c (TARGET_SAVE_ACC_REGISTER): If not defined,
	make it zero.
	* config/rx/rx.h (ASM_APP_ON): Allow to be overridden.
	(ASM_APP_OFF): Likewise.
	* config/rx/rx.opt: Drop -msim and -mas100-syntax, they were
	moved elsewhere.

	* config.host (rx-*-linux*): Add new case.
	* config/rx/t-rx (HOST_LIBGCC2_CFLAGS): Force DFmode to SFmode.

From-SVN: r271748