Add missing libssl dependency on libcrypto

Without this dependency, libssl link is failing with -no-undefined
linker flag.

Change-Id: I9add8687f6493c91d638b2cb458b663cfefc6a74
diff --git a/BUILD.gn b/BUILD.gn
index 753efd3..34a0d63 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -378,6 +378,9 @@
   ]
   public_configs = [ ":boringssl_config" ]
   configs += [ ":internal_config" ]
+  deps = [
+    ":crypto",
+  ]
 }
 
 group("boringssl") {