aix: fix data race in uv_fs_event_start()
aix: fix data race in uv_fs_event_start()

Don't use a buffer with static lifetime to store intermediate results,
use a stack-allocated one.

PR-URL: https://github.com/libuv/libuv/pull/2065
Reviewed-By: Refael Ackermann <0604a90ccdde7a0adfa2ff3857349859a7209740@gmail.com>
Reviewed-By: Richard Lau <8193d74c06330af7778ef55510160e4e561ed6a1@uk.ibm.com>

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