Fix modules build with shared library.

r341994 caused clangAnalysis to pull all of the AST matchers
library into clang. Due to inline key functions in the headers,
importing the AST matchers library gives a link dependency on the
AST matchers (and thus the AST), which clang should not
have.

This patch works around the issues by excluding the offending
libclangAnalysis header in the modulemap.

llvm-svn: 342827