Bug 1224408 - Print yasm version. r=mshal

Report the detected yasm version so logs show what was present.

configure.in

@@ -3500,12 +3500,14 @@ AC_MSG_CHECKING([for YASM assembler])
 AC_CHECK_PROGS(YASM, yasm, "")
 
 if test -n "$YASM"; then
+  AC_MSG_CHECKING([yasm version])
   dnl Pull out yasm's version string
   YASM_VERSION=`yasm --version | $AWK '/^yasm/ { print $2 }'`
   _YASM_MAJOR_VERSION=`echo ${YASM_VERSION} | $AWK -F\. '{ print $1 }'`
   _YASM_MINOR_VERSION=`echo ${YASM_VERSION} | $AWK -F\. '{ print $2 }'`
   _YASM_RELEASE=`      echo ${YASM_VERSION} | $AWK -F\. '{ print $3 }'`
   _YASM_BUILD=`        echo ${YASM_VERSION} | $AWK -F\. '{ print $4 }'`
+  AC_MSG_RESULT([$YASM_VERSION (v$_YASM_MAJOR_VERSION.$_YASM_MINOR_VERSION.$_YASM_RELEASE)])
 fi
 
 if test -z "$SKIP_LIBRARY_CHECKS"; then