Fix compilation on SmartOS/solaris (#2)

Author: Licenser

rebar.config

@@ -7,7 +7,7 @@
 {port_env, [
   {"DRV_LDFLAGS","-shared $ERL_LDFLAGS -lpthread"},
   {"darwin", "DRV_LDFLAGS", "-bundle -flat_namespace -undefined suppress $ERL_LDFLAGS -lpthread"},
-  {"solaris", "ERL_CFLAGS", "-lnsl $ERL_CFLAGS"},
+  {"solaris", "ERL_LDFLAGS", "-lnsl $ERL_LDFLAGS"},
   {"DRV_CFLAGS","-Ic_src -Wall -fPIC $ERL_CFLAGS"},
   {"LDFLAGS", "$LDFLAGS -lpthread"}
 ]}.