Changes look fine to me now. Duplicating the patch is a little sad but I know how clunky it is to reuse patches across ports, so for something this simple so be it.
Unconditionally using ../gettext-runtime in the patch paths allowed me to use EXTRA_PATCHES in gettext-tools to resolve this.
Unconditionally using ../gettext-runtime in the patch paths allowed me to use EXTRA_PATCHES in gettext-tools to resolve this.