[docs] Document LLVM_{BUILD,LINK}_LLVM_DYLIB

Summary:
Document the LLVM_BUILD_LLVM_DYLIB and LLVM_LINK_LLVM_DYLIB
CMake options, move BUILD_SHARED_LIBS out of frequently-used,
and add a note/warning to BUILD_SHARED_LIBS.

Reviewers: beanz, delcypher, mjacob

Subscribers: mjacob, llvm-commits

Differential Revision: http://reviews.llvm.org/D16208

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257864 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed