build: ibmi support for cmake
build: ibmi support for cmake

PR-URL: https://github.com/libuv/libuv/pull/2729
Reviewed-By: Ben Noordhuis <59bd0a3ff43b32849b319e645d4798d8a5d1e889@bnoordhuis.nl>
Reviewed-By: Michael Dawson <241bf52ebd97cc4ec83d57b04d1f9e9053df032e@ca.ibm.com>
Reviewed-By: Kevin Adler <927504b537f6137f8015f3612ffb8e8197eb6ad2@us.ibm.com>
Reviewed-By: Richard Lau <8193d74c06330af7778ef55510160e4e561ed6a1@uk.ibm.com>

unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso