Move cper.c from drivers/acpi/apei to drivers/firmware/efi

cper.c contains code to decode and print "Common Platform Error Records".
Originally added under drivers/acpi/apei because the only user was in that
same directory - but now we have another consumer, and we shouldn't have
to force CONFIG_ACPI_APEI get access to this code.

Since CPER is defined in the UEFI specification - the logical home for
this code is under drivers/firmware/efi/

Acked-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index b0fc7c7..3150aa4 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -36,4 +36,7 @@
 	  backend for pstore by default. This setting can be overridden
 	  using the efivars module's pstore_disable parameter.
 
+config UEFI_CPER
+	def_bool n
+
 endmenu