cmd: efidebug: add missing efi_free_pool for dh subcommand

This adds the missing efi_free_pool call for dh subcommand.

Fixes: a80146205d ("cmd: efidebug: add dh command")
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

cmd/efidebug.c

@@ -486,6 +486,7 @@ static int do_efi_show_handles(struct cmd_tbl *cmdtp, int flag,
 			if (guidcmp(guid[j], &efi_guid_device_path))
 				printf("  %pUs\n", guid[j]);
 		}
+		efi_free_pool(guid);
 	}
 
 	efi_free_pool(handles);