apt: use apt-cache for collecting package specific version

It is needed to specify not only source version but also
distribution specific one (such as 5.5.28-0ubuntu0.12.04.2) to
 force specific MySQL version

packages/apt/build-deb.sh

@@ -121,16 +121,9 @@ tar xfz ${PACKAGE}_${VERSION}.orig.tar.gz
 cd ${PACKAGE}-${VERSION}/
 cp -rp /tmp/${PACKAGE}-debian debian
 # export DEB_BUILD_OPTIONS="noopt nostrip"
-case \$MYSQL_SOURCE_DIR in
-  *mysql-5.1*)
-  MYSQL_SOURCE_VERSION=\${MYSQL_SOURCE_DIR##./mysql-5.1-}
-  sed -i "s/@VERSION@/\$MYSQL_SOURCE_VERSION/" debian/control
-  ;;
-  *mysql-5.5*)
-  MYSQL_SOURCE_VERSION=\${MYSQL_SOURCE_DIR##./mysql-5.5-}
-  sed -i "s/@VERSION@/\$MYSQL_SOURCE_VERSION/" debian/control
-  ;;
-esac
+MYSQL_PACKAGE_INFO=\$(apt-cache show mysql-server | grep Version | sort | tail -1)
+MYSQL_PACKAGE_VERSION=\${MYSQL_PACKAGE_INFO##Version: }
+sed -i "s/@VERSION@/\$MYSQL_PACKAGE_VERSION/" debian/control
 debuild -us -uc
 EOF