MdeModulePkg/RegularExpressinoDxe: Fix clang error #5

Job	Run time
Analyze (ArmPkg, IA32,X64)	3m 31s
Analyze (CryptoPkg, IA32)	15m 19s
Analyze (CryptoPkg, X64)	17m 11s
Analyze (DynamicTablesPkg, IA32,X64)	4m 0s
Analyze (FatPkg, IA32,X64)	10m 41s
Analyze (FmpDevicePkg, IA32,X64)	13m 41s
Analyze (IntelFsp2Pkg, IA32,X64)	9m 56s
Analyze (IntelFsp2WrapperPkg, IA32,X64)	10m 23s
Analyze (MdeModulePkg, IA32)	25m 19s
Analyze (MdeModulePkg, X64)	15m 44s
Analyze (MdePkg, IA32,X64)	16m 19s
Analyze (PcAtChipsetPkg, IA32,X64)	12m 10s
Analyze (PrmPkg, IA32,X64)	11m 58s
Analyze (SecurityPkg, IA32,X64)	18m 24s
Analyze (ShellPkg, IA32,X64)	14m 2s
Analyze (SourceLevelDebugPkg, IA32,X64)	13m 6s
Analyze (StandaloneMmPkg, IA32,X64)	10m 52s
Analyze (UefiCpuPkg, IA32,X64)	19m 45s
Analyze (UnitTestFrameworkPkg, IA32,X64)	10m 26s
	4h 12m 47s

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