Add AC_SEARCH_LIBS stanzas for kqueue and pthread_workqueue#12

dgrove-oss wants to merge 1 commit intoswiftlang:masterswiftlang/swift-corelibs-libdispatch:masterfrom

dgrove-oss:autoconf-lib-searchdgrove-oss/swift-corelibs-libdispatch:autoconf-lib-searchCopy head branch name to clipboard