efi/arm64: efistub: remove local copy of linux_banner

The shared efistub code for ARM and arm64 contains a local copy of
linux_banner, allowing it to be referenced from separate executables
such as the ARM decompressor. However, this introduces a dependency on
generated header files, causing unnecessary rebuilds of the stub itself
and, in case of arm64, vmlinux which contains it.

On arm64, the copy is not actually needed since we can reference the
original symbol directly, and as it turns out, there may be better ways
to deal with this for ARM as well, so let's remove it from the shared
code. If it still needs to be reintroduced for ARM later, it should live
under arch/arm anyway and not in shared code.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

arch/arm64/kernel/efi-stub.c

@@ -12,8 +12,6 @@
 #include <linux/efi.h>
 #include <linux/libfdt.h>
 #include <asm/sections.h>
-#include <generated/compile.h>
-#include <generated/utsrelease.h>
 
 /*
  * AArch64 requires the DTB to be 8-byte aligned in the first 512MiB from

drivers/firmware/efi/fdt.c

@@ -23,16 +23,6 @@ static efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
 	u32 fdt_val32;
 	u64 fdt_val64;
 
-	/*
-	 * Copy definition of linux_banner here.  Since this code is
-	 * built as part of the decompressor for ARM v7, pulling
-	 * in version.c where linux_banner is defined for the
-	 * kernel brings other kernel dependencies with it.
-	 */
-	const char linux_banner[] =
-	    "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@"
-	    LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n";
-
 	/* Do some checks on provided FDT, if it exists*/
 	if (orig_fdt) {
 		if (fdt_check_header(orig_fdt)) {