build: do not consult the legacy staging location for libdispatch

Use the proper output location from CMake for linking.  This will allow us to
clean up the staging from the libdispatch build system.

Author: compnerd

build.py

@@ -126,7 +126,7 @@
 		'-I'+Configuration.current.variables["LIBDISPATCH_BUILD_DIR"]+'/src/swift',
 		'-Xcc -fblocks'
 	])
-	foundation.LDFLAGS += '-ldispatch -L'+Configuration.current.variables["LIBDISPATCH_BUILD_DIR"]+'/src/.libs -rpath \$$ORIGIN '
+	foundation.LDFLAGS += '-ldispatch -L'+Configuration.current.variables["LIBDISPATCH_BUILD_DIR"]+'/src -rpath \$$ORIGIN '
 	foundation.LDFLAGS += '-L' + Configuration.current.variables['LIBDISPATCH_BUILD_DIR'] + ' -lBlocksRuntime '
 
 foundation.SWIFTCFLAGS = " ".join(swift_cflags)
@@ -541,7 +541,7 @@
         'TestFoundation/Utilities.swift',
 ] + glob.glob('./TestFoundation/Test*.swift')) # all TestSomething.swift are considered sources to the test project in the TestFoundation directory
 
-Configuration.current.extra_ld_flags += ' -L'+Configuration.current.variables["LIBDISPATCH_BUILD_DIR"]+'/src/.libs'
+Configuration.current.extra_ld_flags += ' -L'+Configuration.current.variables["LIBDISPATCH_BUILD_DIR"]+'/src'
 
 foundation_tests.add_dependency(foundation_tests_resources)
 xdgTestHelper = SwiftExecutable('xdgTestHelper',
@@ -561,7 +561,7 @@
 if "XCTEST_BUILD_DIR" in Configuration.current.variables:
     LIBS_DIRS += "${XCTEST_BUILD_DIR}:"
 if "LIBDISPATCH_BUILD_DIR" in Configuration.current.variables:
-    LIBS_DIRS += Configuration.current.variables["LIBDISPATCH_BUILD_DIR"]+"/src/.libs:"
+    LIBS_DIRS += Configuration.current.variables["LIBDISPATCH_BUILD_DIR"]+"/src:"
 
 Configuration.current.variables["LIBS_DIRS"] = LIBS_DIRS