Add dependencies on a few system libraries.

These libraries moved out of the sysroot.

Change-Id: Ie06492c13bfd133708ecd584fd7d02fb2c416c4b
diff --git a/BUILD.gn b/BUILD.gn
index 8ea3bb3..7e3fde4 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -70,6 +70,10 @@
     "fuchsia/fuchsia-compat.c",
     "fuchsia/fuchsia-compat.h",
   ]
+  public_deps = [
+    "//zircon/public/lib/fdio",
+    "//zircon/public/lib/launchpad",
+  ]
   configs += [ ":fuchsia" ]
 }
 
@@ -261,7 +265,6 @@
     ":umac128",
     "//third_party/boringssl",
   ]
-  libs = [ "launchpad" ]
   configs += [ ":fuchsia" ]
 }
 
@@ -358,6 +361,10 @@
     ":fuchsia",
     ":openbsd-compat-config",
   ]
+  public_deps = [
+    "//zircon/public/lib/fdio",
+    "//zircon/public/lib/launchpad",
+  ]
 }
 
 executable("ssh") {