MdeModulePkg/Core/Dxe: Remove extra connects for UEFI Applications

MdeModulePkg/Core/Dxe: Remove extra connects for UEFI Applications

https://bugzilla.tianocore.org/show_bug.cgi?id=765

The UEFI Specification Boot Services chapter, StartImage() service,
EFF 1.10 Extension requires extra calls to ConnectController()
if a UEFI Driver produces handles. The DXE Core is performing these
extra calls to ConnectController() without evaluating the ImageType.

A filter is added to not make extra calls to ConnectController()
if the ImageType is EFI_IMAGE_SUBSYSTEM_EFI_APPLICATION.

Without this filter, extra calls to ConnectController() may be
performed by UEFI Applications or a UEFI Shell Applications that
also call ConnectController().

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>