EmulatorPkg/MiscSubClassPlatformDxe: Remove this unused module

EmulatorPkg/MiscSubClassPlatformDxe: Remove this unused module

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1953

For commit 63f9b9b9312f3e08c92a2ea3cdbe01e723ef653b, the use of module
EmulatorPkg/MiscSubClassPlatformDxe/MiscSubClassDriver.inf

was replaced by:
EmulatorPkg/PlatformSmbiosDxe/PlatformSmbiosDxe.inf

in platform DSC/FDF files.

This commit will remove this unused module from EmulatorPkg.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Andrew Fish <afish@apple.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Hao A Wu <hao.a.wu@intel.com>