UefiPayloadPkg: Enhance ReadMe.md for ELF and FIT #530

Job	Run time
Analyze (ArmPkg, IA32,X64)	4m 7s
Analyze (CryptoPkg, IA32)	18m 0s
Analyze (CryptoPkg, X64)	17m 19s
Analyze (DynamicTablesPkg, IA32,X64)	9m 24s
Analyze (FatPkg, IA32,X64)	9m 15s
Analyze (FmpDevicePkg, IA32,X64)	9m 49s
Analyze (IntelFsp2Pkg, IA32,X64)	9m 12s
Analyze (IntelFsp2WrapperPkg, IA32,X64)	10m 40s
Analyze (MdeModulePkg, IA32)	11m 56s
Analyze (MdeModulePkg, X64)	17m 17s
Analyze (MdePkg, IA32,X64)	12m 58s
Analyze (PcAtChipsetPkg, IA32,X64)	10m 39s
Analyze (PrmPkg, IA32,X64)	12m 0s
Analyze (SecurityPkg, IA32,X64)	29m 33s
Analyze (ShellPkg, IA32,X64)	11m 1s
Analyze (SourceLevelDebugPkg, IA32,X64)	8m 31s
Analyze (StandaloneMmPkg, IA32,X64)	8m 25s
Analyze (UefiCpuPkg, IA32,X64)	14m 10s
Analyze (UnitTestFrameworkPkg, IA32,X64)	8m 31s
	3h 52m 47s

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