BaseTools: StructurePcd array Value support flexible format

BaseTools: StructurePcd array Value support flexible format

if StructurePcd set item value is array, support flexible format
like as:
gEfiStructuredPcdPkgTokenSpaceGuid.Test.Array | {flexible format}
{flexible format} = {L"ABC"} | {L'ABC'} | {"ABC"} | {UINT8(0x10)}
                  | {UINT16(0x10)} | {UINT32(0x10)} | {UINT64(0x10)}
                  | {DEVICE_PATH("PciRoot(0)/Pci(0,0)")}
                  | {GUID(gPcdPkgTokenSpaceGuid)}
                  | {L"ABC", L'ABC', UINT8(0x10)....}

Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Yunhua Feng <yunhuax.feng@intel.com>
Reviewed-by: Yonghong Zhu <yonghong.zhu@intel.com>