build: Let PKG_CONFIG_PATH shine though

dlespiau · dlespiau · commit 337422980294 · 2018-11-03T13:12:20.000Z
When specifying the pc extension with v8.pc, pkg-config will not look at the
usual directories but only look at the current directory for a file named
v8.pc.
diff --git a/worker.go b/worker.go
@@ -23,7 +23,7 @@ package v8worker2
 
 /*
 #cgo CXXFLAGS: -std=c++11
-#cgo pkg-config: v8.pc
+#cgo pkg-config: v8
 #include <stdlib.h>
 #include "binding.h"
 */
