Remove an unused parameter from the dlopen implementation.

Change-Id: I9297913a743bb570b48ebbe594ff711a481e89e0
diff --git a/linker/linker.cpp b/linker/linker.cpp
index 5452f30..a22233d 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -827,7 +827,7 @@
   }
 }
 
-soinfo* do_dlopen(const char* name, int flags, soinfo* /*caller*/, const android_dlextinfo* extinfo) {
+soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo) {
   if ((flags & ~(RTLD_NOW|RTLD_LAZY|RTLD_LOCAL|RTLD_GLOBAL|RTLD_NOLOAD)) != 0) {
     DL_ERR("invalid flags to dlopen: %x", flags);
     return NULL;