efi_loader: fix CapsuleMax variable reporting

Currently the code that adds the CapsuleMax variable is under a
Kconfig named 'EFI_HAVE_CAPSULE_UPDATE.  Git history only shows a
single occurrence of that.  The IS_ENABLED should be checking for
EFI_HAVE_CAPSULE_SUPPORT

Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
index 5437641..f0f01d3 100644
--- a/lib/efi_loader/efi_setup.c
+++ b/lib/efi_loader/efi_setup.c
@@ -128,7 +128,7 @@
 {
 	efi_status_t ret = EFI_SUCCESS;
 
-	if (IS_ENABLED(CONFIG_EFI_HAVE_CAPSULE_UPDATE)) {
+	if (IS_ENABLED(CONFIG_EFI_HAVE_CAPSULE_SUPPORT)) {
 		ret = efi_set_variable_int(u"CapsuleMax",
 					   &efi_guid_capsule_report,
 					   EFI_VARIABLE_READ_ONLY |