This change moves some ASSERTs in error handling code to improve efficiency in DEBUG build. This change also removes redundant error code returns. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Girish Pathak <girish.pathak@arm.com> Signed-off-by: Evan Lloyd <evan.lloyd@arm.com> Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>