x86: Include bss subsections in linker script

When we build with -fdata-sections we may end up with bss subsections. Our
linker script explicitly lists only a single consecutive bss section though.

Adapt the statement to also include subsections.

This fixes booting efi-x86_app_defconfig.

Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/x86/cpu/u-boot.lds b/arch/x86/cpu/u-boot.lds
index a1cc19c..a283c29 100644
--- a/arch/x86/cpu/u-boot.lds
+++ b/arch/x86/cpu/u-boot.lds
@@ -94,7 +94,7 @@
 
 	.bss __rel_dyn_start (OVERLAY) : {
 		__bss_start = .;
-		*(.bss)
+		*(.bss*)
 		*(COM*)
 		. = ALIGN(4);
 		__bss_end = .;