LDSCRIPT: Name INIT_RAM_FS consistently

LDSCRIPT: Name INIT_RAM_FS consistently

In asm-generic/vmlinux.lds.h, name INIT_RAM_FS consistently, no matter the
setting of CONFIG_BLK_DEV_INITRD.  This corrects:

	commit ef53dae8658cf0e93d380983824a661067948d87
	Author: Sam Ravnborg <[email protected]>
	Date:   Sun Jun 7 20:46:37 2009 +0200
	Subject: Improve vmlinux.lds.h support for arch specific linker scripts

Signed-off-by: David Howells <[email protected]>
Acked-by: Sam Ravnborg <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>