MdePkg Base.h: Define STATIC_ASSERT macro as empty for EBC arch

MdePkg Base.h: Define STATIC_ASSERT macro as empty for EBC arch

EBC compiler doesn't support C11 static_assert macro.
So, define STATIC_ASSERT as empty to pass EBC arch build.
STATIC_ASSERT macro is introduced @204ae9da230ecbf0910c21acac7aa5d5e8cbb8d0

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Signed-off-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>