Darwin: mark test unsupported while we sort out how to make it generic.

This test relies on communicating with debugserver via an unnamed (pre-opened)
pipe, but macOS's version of debugserver doesn't seem to support that mode of
operation. So disable the test for now.

llvm-svn: 339343

lldb/lit/tools/lldb-mi/target/target-select-so-path.test

@@ -1,4 +1,4 @@
-# UNSUPPORTED: windows
+# UNSUPPORTED: windows, darwin
 #
 # RUN: %cc -o %t %p/inputs/main.c -g
 # RUN: python %p/inputs/target-select-so-path.py "%debugserver" "%lldbmi %t" %s