BaseTools: Fix the bug for RAW file alignment value support

BaseTools: Fix the bug for RAW file alignment value support

Fix the bug for RAW file to support Align=32 and Align=64. Current FDF
spec FfsAlignmentValues support this two values, while it is not the
valid value for GenFfs. So this patch add the logic to handle it.

Fixes: https://bugzilla.tianocore.org/show_bug.cgi?id=248
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Yonghong Zhu <yonghong.zhu@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>