Rename coreboot_ram stage to ramstage

Rename coreboot_ram stage to ramstage. This is done in order to provide
consistency with other stage names (bootblock, romstage) and to allow any
Makefile rule generalization, required for patches to be submitted later.

Change-Id: Ib66e43b7e17b9c48b2d099670ba7e7d857673386
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: http://review.coreboot.org/5567
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

src/lib/rmodule.ld

@@ -34,7 +34,7 @@ SECTIONS
 
 		/* The driver sections are to allow linking coreboot's
 		 * ramstage with the rmodule linker. Any changes made in
-		 * coreboot_ram.ld should be made here as well. */
+		 * ramstage.ld should be made here as well. */
 		pci_drivers = . ;
 		*(.rodata.pci_driver)
 		epci_drivers = . ;