[SPARK-20123][BUILD] SPARK_HOME variable might have spaces in it(e.g. $SPARK…

JIRA Issue: https://issues.apache.org/jira/browse/SPARK-20123

## What changes were proposed in this pull request?

If $SPARK_HOME or $FWDIR variable contains spaces, then use "./dev/make-distribution.sh --name custom-spark --tgz -Psparkr -Phadoop-2.7 -Phive -Phive-thriftserver -Pmesos -Pyarn" build spark will failed.

## How was this patch tested?

manual tests

Author: zuotingbing <zuo.tingbing9@zte.com.cn>

Closes #17452 from zuotingbing/spark-bulid.