Changes:
38cfa2e Up the release version to 2.64
7617af6 Avoid a deadlock in forked psx thread exit.
fc029cb Include LIBCAP_{MAJOR,MINOR} #define's in sys/capability.h
ceaa591 Clarify how the cap_get_pid() argument is interpreted.
15cacf2 Fix prctl return code/errno handling in libcap.
aae9374 Be explicit about CGO_ENABLED=1 for compare-cap build.
66a8a14 psx: free allocated memory at exit.
Signed-off-by: Nick Hainke <vincent@systemli.org>