userspace: properly namespace handler functions

Now prefixed with z_hdlr_ instead of just hdlr_.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
diff --git a/scripts/gen_syscall_header.py b/scripts/gen_syscall_header.py
index 50fa4a2..ff31288 100755
--- a/scripts/gen_syscall_header.py
+++ b/scripts/gen_syscall_header.py
@@ -81,7 +81,7 @@
     # from gc-sections; these references will not consume space.
 
     sys.stdout.write(
-        "static Z_GENERIC_SECTION(hndlr_ref) __used void *href = (void *)&hdlr_##name; \\\n")
+        "static Z_GENERIC_SECTION(hndlr_ref) __used void *href = (void *)&z_hdlr_##name; \\\n")
     tabs(tabcount)
     if (ret != Retval.VOID):
         sys.stdout.write("return (ret)")