arch/x86/Kconfig: Move pagetables down by 4K

In case of 64K bootblock the pagetables don't fit, as the CBFS header
also needs a few bytes.

Fixes build error on platforms that use 64KiB bootblock.
Tested on Lenovo T410 with additional x86_64 patches.

Change-Id: I854c5f575e2376827a366cca8d25682c4d90bc8f
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37394
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/arch/x86/Kconfig b/src/arch/x86/Kconfig
index 0346c71..900c9c1 100644
--- a/src/arch/x86/Kconfig
+++ b/src/arch/x86/Kconfig
@@ -69,7 +69,7 @@
 config ARCH_X86_64_PGTBL_LOC
 	hex "x86_64 page table location in CBFS"
 	depends on ARCH_BOOTBLOCK_X86_64
-	default 0xfffea000
+	default 0xfffe9000
 	help
 	  The position where to place pagetables. Needs to be known at
 	  compile time. Must not overlap other files in CBFS.