Mark generated cgen files read-only

	* cgen.sh: Mark generated files read-only.
	* epiphany-asm.c: Regenerate.
	* epiphany-desc.c: Regenerate.
	* epiphany-desc.h: Regenerate.
	* epiphany-dis.c: Regenerate.
	* epiphany-ibld.c: Regenerate.
	* epiphany-opc.c: Regenerate.
	* epiphany-opc.h: Regenerate.
	* fr30-asm.c: Regenerate.
	* fr30-desc.c: Regenerate.
	* fr30-desc.h: Regenerate.
	* fr30-dis.c: Regenerate.
	* fr30-ibld.c: Regenerate.
	* fr30-opc.c: Regenerate.
	* fr30-opc.h: Regenerate.
	* frv-asm.c: Regenerate.
	* frv-desc.c: Regenerate.
	* frv-desc.h: Regenerate.
	* frv-dis.c: Regenerate.
	* frv-ibld.c: Regenerate.
	* frv-opc.c: Regenerate.
	* frv-opc.h: Regenerate.
	* ip2k-asm.c: Regenerate.
	* ip2k-desc.c: Regenerate.
	* ip2k-desc.h: Regenerate.
	* ip2k-dis.c: Regenerate.
	* ip2k-ibld.c: Regenerate.
	* ip2k-opc.c: Regenerate.
	* ip2k-opc.h: Regenerate.
	* iq2000-asm.c: Regenerate.
	* iq2000-desc.c: Regenerate.
	* iq2000-desc.h: Regenerate.
	* iq2000-dis.c: Regenerate.
	* iq2000-ibld.c: Regenerate.
	* iq2000-opc.c: Regenerate.
	* iq2000-opc.h: Regenerate.
	* lm32-asm.c: Regenerate.
	* lm32-desc.c: Regenerate.
	* lm32-desc.h: Regenerate.
	* lm32-dis.c: Regenerate.
	* lm32-ibld.c: Regenerate.
	* lm32-opc.c: Regenerate.
	* lm32-opc.h: Regenerate.
	* lm32-opinst.c: Regenerate.
	* m32c-asm.c: Regenerate.
	* m32c-desc.c: Regenerate.
	* m32c-desc.h: Regenerate.
	* m32c-dis.c: Regenerate.
	* m32c-ibld.c: Regenerate.
	* m32c-opc.c: Regenerate.
	* m32c-opc.h: Regenerate.
	* m32r-asm.c: Regenerate.
	* m32r-desc.c: Regenerate.
	* m32r-desc.h: Regenerate.
	* m32r-dis.c: Regenerate.
	* m32r-ibld.c: Regenerate.
	* m32r-opc.c: Regenerate.
	* m32r-opc.h: Regenerate.
	* m32r-opinst.c: Regenerate.
	* mep-asm.c: Regenerate.
	* mep-desc.c: Regenerate.
	* mep-desc.h: Regenerate.
	* mep-dis.c: Regenerate.
	* mep-ibld.c: Regenerate.
	* mep-opc.c: Regenerate.
	* mep-opc.h: Regenerate.
	* mt-asm.c: Regenerate.
	* mt-desc.c: Regenerate.
	* mt-desc.h: Regenerate.
	* mt-dis.c: Regenerate.
	* mt-ibld.c: Regenerate.
	* mt-opc.c: Regenerate.
	* mt-opc.h: Regenerate.
	* or1k-asm.c: Regenerate.
	* or1k-desc.c: Regenerate.
	* or1k-desc.h: Regenerate.
	* or1k-dis.c: Regenerate.
	* or1k-ibld.c: Regenerate.
	* or1k-opc.c: Regenerate.
	* or1k-opc.h: Regenerate.
	* or1k-opinst.c: Regenerate.
	* xc16x-asm.c: Regenerate.
	* xc16x-desc.c: Regenerate.
	* xc16x-desc.h: Regenerate.
	* xc16x-dis.c: Regenerate.
	* xc16x-ibld.c: Regenerate.
	* xc16x-opc.c: Regenerate.
	* xc16x-opc.h: Regenerate.
	* xstormy16-asm.c: Regenerate.
	* xstormy16-desc.c: Regenerate.
	* xstormy16-desc.h: Regenerate.
	* xstormy16-dis.c: Regenerate.
	* xstormy16-ibld.c: Regenerate.
	* xstormy16-opc.c: Regenerate.
	* xstormy16-opc.h: Regenerate.