MdePkg/Library/BaseStackCheckLib: Fix PCD type in INF

MdePkg/Library/BaseStackCheckLib: Fix PCD type in INF

Update INF file to use a [Pcd] section instead of a
[FixedPcd] section.  [FixedPcd] should only be used in an
INF file if the source code looks up the PCD value using
the PcdLib FixedPcdGetxx() services.  Using [FixedPcd]
forces a platform to configure the PCD to type FixedAtBuild.
In this case, PcdDebugPropertyMask supports PCD types
FixedAtBuild and PatchableInModule.  Without this change
any platform that wants to use PcdDebugPropertyMask as
type PatchableInModule breaks the build.

Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>