Name function arguments in libc headers for Studio.

Second batch of headers...

Bug: http://b/64613623
Test: builds
Change-Id: I8eef043dbf32afee8ff814e9d005f46aee8fa21f
diff --git a/libc/include/dlfcn.h b/libc/include/dlfcn.h
index 76bbdb8..68d8bc9 100644
--- a/libc/include/dlfcn.h
+++ b/libc/include/dlfcn.h
@@ -45,12 +45,12 @@
   void* dli_saddr;
 } Dl_info;
 
-void* dlopen(const char* filename, int flag);
-int dlclose(void* handle);
+void* dlopen(const char* __filename, int __flag);
+int dlclose(void* __handle);
 char* dlerror(void);
-void* dlsym(void* handle, const char* symbol);
-void* dlvsym(void* handle, const char* symbol, const char* version) __INTRODUCED_IN(24);
-int dladdr(const void* addr, Dl_info* info);
+void* dlsym(void* __handle, const char* __symbol);
+void* dlvsym(void* __handle, const char* __symbol, const char* __version) __INTRODUCED_IN(24);
+int dladdr(const void* __addr, Dl_info* __info);
 
 #define RTLD_LOCAL    0
 #define RTLD_LAZY     0x00001
@@ -77,4 +77,4 @@
 
 __END_DECLS
 
-#endif /* __DLFCN_H */
+#endif