MdeModulePkg/scsi :Coverity scan flags multiple issues in edk2-stable202205

Added changes to resolve the SCSI driver Coverity issues.

Cc: Vasudevan Sambandan <vasudevans@ami.com>
Cc: Sundaresan Selvaraj <sundaresans@ami.com>
Signed-off-by: Sivaparvathi chellaiah <sivaparvathic@ami.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>