[CMake] Don't install libllbuild in the Swift toolchain now that it's statically linked

Now that libllbuildSwift is statically linked against libllbuild with #852,
remove the runpath and don't install it. Also, the Android build started
failing, so set the appropriate flag for it to work again.

Author: finagolfin

CMakeLists.txt

@@ -51,6 +51,9 @@ else()
   endif()
 endif()
 
+if(CMAKE_SYSTEM_NAME STREQUAL Android)
+  set(CMAKE_HAVE_LIBC_PTHREAD TRUE)
+endif()
 set(THREADS_PREFER_PTHREAD_FLAG FALSE)
 find_package(Threads REQUIRED)
 

products/libllbuild/CMakeLists.txt

@@ -57,14 +57,6 @@ install(TARGETS libllbuild
   RUNTIME DESTINATION bin
   COMPONENT libllbuild)
 
-if(Swift IN_LIST LLBUILD_SUPPORT_BINDINGS)
-  if(NOT CMAKE_SYSTEM_NAME STREQUAL Windows)
-    install(TARGETS libllbuild
-      DESTINATION lib/swift/pm/llbuild
-      COMPONENT libllbuildSwift)
-  endif()
-endif()
-
 add_custom_target(install-libllbuild
                   DEPENDS libllbuild
                   COMMENT "Installing libllbuild..."

products/llbuildSwift/CMakeLists.txt

@@ -65,7 +65,7 @@ else()
   if(NOT CMAKE_SYSTEM_NAME STREQUAL Windows)
     target_link_options(llbuildSwift PRIVATE "SHELL:-no-toolchain-stdlib-rpath")
     set_target_properties(llbuildSwift PROPERTIES
-      INSTALL_RPATH "$ORIGIN:$ORIGIN/../../$<LOWER_CASE:${CMAKE_SYSTEM_NAME}>")
+      INSTALL_RPATH "$ORIGIN/../../$<LOWER_CASE:${CMAKE_SYSTEM_NAME}>")
   endif()
 endif()
 set_target_properties(llbuildSwift PROPERTIES