autoconf: Test FREAD_READS_DIRECTORIES
Add test for FREAD_READS_DIRECTORIES to detect when fread() reads fopen'ed
directory.
Tested on these platforms:
AIX 5.3 - FREAD_READS_DIRECTORIES=UnfortunatelyYes
HP-UX B.11.11 - FREAD_READS_DIRECTORIES=UnfortunatelyYes
HP-UX B.11.23 - FREAD_READS_DIRECTORIES=UnfortunatelyYes
Linux 2.6.25-rc4 - FREAD_READS_DIRECTORIES=
Tru64 V5.1 - FREAD_READS_DIRECTORIES=UnfortunatelyYes
Windows - FREAD_READS_DIRECTORIES=
Signed-off-by: Michal Rokos <redacted>
Tested-by: Mike Ralphson <redacted>
Tested-by: Johannes Schindelin <redacted>
Signed-off-by: Junio C Hamano <redacted>