[llvm-exegesis] Add support for instructions with memory operands (latency mode)

[llvmbot]

Bugzilla Link	36905
Version	trunk
OS	Linux
Blocks	#35432
Reporter	LLVM Bugzilla Contributor
CC	@LebedevRI,@RKSimon

Extended Description

See discussion here: https://reviews.llvm.org/D44654

[llvmbot]

assigned to @gchatelet