efi: stub: add known memory to U-Boot's EFI memory map

When running U-Boot as an EFI payload with CONFIG_EFI_STUB, the reserved
regions from the previous stage EFI bootloader should be carried over
since they may not fully align with the reserved-memory regions in
devicetree.

Implement a helper to map these pages when the EFI subsystem starts up.

Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>

lib/efi_loader/efi_memory.c

@@ -9,6 +9,7 @@
 
 #include <efi_loader.h>
 #include <efi_log.h>
+#include <efi_stub.h>
 #include <init.h>
 #include <lmb.h>
 #include <log.h>
@@ -830,6 +831,10 @@ int efi_memory_init(void)
 {
 	efi_add_known_memory();
 
+#ifdef CONFIG_EFI_STUB
+	efi_add_known_memory_from_efi();
+#endif
+
 	add_u_boot_and_runtime();
 
 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER