x86/efi: fix improper use of lvalue

# HG changeset patch
# User Jeremy Fitzhardinge <jeremy@xensource.com>
# Date 1199391030 28800
# Node ID 5d35c92fdf0e2c52edbb6fc4ccd06c7f65f25009
# Parent  22f6a5902285b58bfc1fbbd9e183498c9017bd78
x86/efi: fix improper use of lvalue

pgd_val is no longer valid as an lvalue, so don't try to assign to it.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/efi_64.c

@@ -85,7 +85,7 @@ void __init efi_call_phys_prelog(void)
 	local_irq_save(efi_flags);
 	early_runtime_code_mapping_set_exec(1);
 	vaddress = (unsigned long)__va(0x0UL);
-	pgd_val(save_pgd) = pgd_val(*pgd_offset_k(0x0UL));
+	save_pgd = *pgd_offset_k(0x0UL);
 	set_pgd(pgd_offset_k(0x0UL), *pgd_offset_k(vaddress));
 	__flush_tlb_all();
 }