BuildSystem: Fix a typo related to ./configure --prefix=<path> on OpenBSD.

Reported by: Stuart Henderson

Change-Id: Ieae8624f48b6ae78cf29930b9a45a3c842c7a764

configure

@@ -4618,7 +4618,7 @@ astvarrundir='${localstatedir}/run/asterisk'
 case "${host_os}" in
      *bsd*)
-     if test ${prefix} = 'NONE'; then
+     if test ${prefix} != 'NONE'; then
         astvarlibdir='${prefix}/share/asterisk'
         astdbdir='${localstatedir}/db/asterisk'
      fi

configure.ac

@@ -49,7 +49,7 @@ AC_SUBST([astvarrundir],      ['${localstatedir}/run/asterisk'])dnl
 
 case "${host_os}" in
      *bsd*)
-     if test ${prefix} = 'NONE'; then
+     if test ${prefix} != 'NONE'; then
         astvarlibdir='${prefix}/share/asterisk'
         astdbdir='${localstatedir}/db/asterisk'
      fi