Update parsing of MAKE_FLAGS in DSC [BuildOptions] sections
to split the flags into a list to be compatible with
running the make command using Popen(). Parsing MAKE_FLAGS
from tools_def.txt already uses _SplitOption(). This change
uses the same _SplitOption() method for MAKE_FLAGS from a
DSC [BuildOptions] section.
Also update the parsing of MAKE_PATH to support MAKE_PATH
from tools_def.txt or the DSC [BuildOptions] section. MAKE_PATH
in DSC [BuildOptions] section is higher priority than MAKE_PATH
in tools_def.txt.
Cc: Bob Feng <bob.c.feng@intel.com> Cc: Liming Gao <gaoliming@byosoft.com.cn> Cc: Yuwei Chen <yuwei.chen@intel.com> Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com> Reviewed-by: Yuwei Chen <yuwei.chen@intel.com> Reviewed-by: Bob Feng <bob.c.feng@intel.com>