ShellPkg: CodeQL Fixes #244

Job	Run time
Analyze (ArmPkg, IA32,X64)	4m 10s
Analyze (CryptoPkg, IA32)	13m 59s
Analyze (CryptoPkg, X64)	14m 44s
Analyze (DynamicTablesPkg, IA32,X64)	14m 31s
Analyze (FatPkg, IA32,X64)	9m 0s
Analyze (FmpDevicePkg, IA32,X64)	12m 1s
Analyze (IntelFsp2Pkg, IA32,X64)	7m 32s
Analyze (IntelFsp2WrapperPkg, IA32,X64)	7m 11s
Analyze (MdeModulePkg, IA32)	13m 55s
Analyze (MdeModulePkg, X64)	19m 12s
Analyze (MdePkg, IA32,X64)	10m 36s
Analyze (PcAtChipsetPkg, IA32,X64)	9m 1s
Analyze (PrmPkg, IA32,X64)	9m 20s
Analyze (SecurityPkg, IA32,X64)	14m 26s
Analyze (ShellPkg, IA32,X64)	12m 54s
Analyze (SourceLevelDebugPkg, IA32,X64)	8m 32s
Analyze (StandaloneMmPkg, IA32,X64)	10m 10s
Analyze (UefiCpuPkg, IA32,X64)	15m 47s
Analyze (UnitTestFrameworkPkg, IA32,X64)	13m 43s
	3h 40m 44s

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