According to QEMU docs, the '-m' option for specifying RAM is by default
in MiB, and a suffix of "M" or "G" may be passed for values in MiB and
GiB respectively. This commit adds support and a test for the same.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=812295
Signed-off-by: Nishith Shah <nishithshah.2211@gmail.com>