configure: luac: autodetect host if not provided
When building the luac contrib, it is built at
$(PREFIX)/../bin/$(cc -dumpmachine)-luac
When configuring, if --host
is not provided, the script looks for luac
at $(PREFIX)/../bin/-luac
as $host_alias
is empty, failing to lookup
luac.
Use (cc -dumpmachine)
to look for the LUA byte compiler when host is not
provided.
Edited by Khalid Masum