efi_loader: make the UEFI boot manager configurable

Some boards are very tight on the binary size. Booting via UEFI is possible
without using the boot manager.

Provide a configuration option to make the boot manager available.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/cmd/efidebug.c b/cmd/efidebug.c
index 6de81ca..9a2d4dd 100644
--- a/cmd/efidebug.c
+++ b/cmd/efidebug.c
@@ -1367,8 +1367,8 @@
  *
  *     efidebug test bootmgr
  */
-static int do_efi_test_bootmgr(struct cmd_tbl *cmdtp, int flag,
-			       int argc, char * const argv[])
+static __maybe_unused int do_efi_test_bootmgr(struct cmd_tbl *cmdtp, int flag,
+					      int argc, char * const argv[])
 {
 	efi_handle_t image;
 	efi_uintn_t exit_data_size = 0;
@@ -1392,8 +1392,10 @@
 }
 
 static struct cmd_tbl cmd_efidebug_test_sub[] = {
+#ifdef CONFIG_CMD_BOOTEFI_BOOTMGR
 	U_BOOT_CMD_MKENT(bootmgr, CONFIG_SYS_MAXARGS, 1, do_efi_test_bootmgr,
 			 "", ""),
+#endif
 };
 
 /**
@@ -1581,8 +1583,10 @@
 	"  - show UEFI memory map\n"
 	"efidebug tables\n"
 	"  - show UEFI configuration tables\n"
+#ifdef CONFIG_CMD_BOOTEFI_BOOTMGR
 	"efidebug test bootmgr\n"
 	"  - run simple bootmgr for test\n"
+#endif
 	"efidebug query [-nv][-bs][-rt][-at]\n"
 	"  - show size of UEFI variables store\n";
 #endif