While here, fix libIlmImfUtil_la_LDFLAGp so that when linking libIlmImfUtil,
the locally built libIlmImf gets precedence over the one in /usr/local,
to permit upgrades in a running system with the older version installed.
This changes the library's SONAME, so bump PORTREVISION of all dependees.
Unfortunately, this looks a bit too intrusive for an MFH to 2017Q4.
Security: CVE-2017-9110
Security: CVE-2017-9111
Security: CVE-2017-9112
Security: CVE-2017-9113
Security: CVE-2017-9114
Security: CVE-2017-9115
Security: CVE-2017-9116
Security: 803879e9-4195-11e7-9b08-080027ef73ec