dracut.spec: only apply patches, if there are any

dracut.spec

@@ -161,6 +161,8 @@ This package contains tools to assemble the local initrd and host configuration.
 
 %prep
 %setup -q -n %{name}-%{version}
+
+%if %{defined PATCH1}
 git init
 git config user.email "dracut-maint@redhat.com"
 git config user.name "Fedora dracut team"
@@ -169,6 +171,7 @@ git commit -a -q -m "%{version} baseline."
 
 # Apply all the patches.
 git am -p1 %{patches}
+%endif
 
 %build
 make