Log Message:
Update mail/clamav to 0.75.1.  Changes from verison 0.75 include:

  - Convert to use bsd.options.mk.
  - The virus database has been moved to ${VARBASE}/clamav.

  * freshclam/clamd:        fix crash on PPC when LogFile was enabled together
                            with LogSyslog
  * configure:              improve gethostbyname_r check; cleanups
  * clamav-milter:          Use GETHOSTBYNAME_R_6
                            Better load balancing if max_children = 0
                            Fixed warning message when building on FreeBSD4.9
                            Closed (small) memory leak
                            Fix crash when the 1st remote service goes down
                            Only use gethostbyname_r on LINUX for now
                            Improved load balancing a bit
  * clamdscan:              fix stdin scanning in local mode
  * clamav-milter:          %v in the template file handling is now replaced
                            only with the virus name, no "stream:" appears
  * libclamav/mbox.c:       Fix crash when debugging on SPARC
  * libclamav/message.c:    Fix occasional crash when scanning
                            multipart within multipart e-mails