MdeModulePkg/UfsPciHc: Avoid overriding return value in BindingStart

MdeModulePkg/UfsPciHc: Avoid overriding return value in BindingStart

In function UfsHcDriverBindingStart(), the return value 'Status' may be
overridden during the original PCI attributes restore process.

This commit refines the logic to avoid such override.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>