llvm-lit should use its current location as the tools-path

[atrick]

Bugzilla Link	15218
Version	trunk
OS	All
CC	@atrick

Extended Description

Currently, if I want to test Debug+Asserts or Release builds, I need to manually edit lit.site.cfg in the build dir, or reconfigure the build, which is even worse.

Shouldn't llvm-lit pick up the tools from it's current build directory? If I run Debug+Asserts/llvm-lit, shouldn't it use Debug+Asserts/clang etc.?

[atrick]

mentioned in issue llvm/llvm-bugzilla-archive#15473