efi_loader: refactor switch to non-secure mode

Refactor the switch from supervisor to hypervisor to a new function called
at the beginning of do_bootefi().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

include/bootm.h

@@ -82,4 +82,9 @@ int bootm_decomp_image(int comp, ulong load, ulong image_start, int type,
  */
 void board_quiesce_devices(void);
 
+/**
+ * switch_to_non_secure_mode() - switch to non-secure mode
+ */
+void switch_to_non_secure_mode(void);
+
 #endif