[cobalt] Remove verbosity

Verbosity has been unsupported for many years on fuchsia,
no viewer supports it and we don't intend to support it.
This change cleans up to use severities instead.

Bug: b/322552971
Bug: b/300157652
Change-Id: If3c288cc839439904c50c822cbb99f83102717ec
Reviewed-on: https://fuchsia-review.googlesource.com/c/cobalt/+/985000
Reviewed-by: Alex Pankhurst <pankhurst@google.com>
Commit-Queue: Brian Bosak <bbosak@google.com>
diff --git a/src/logging.h b/src/logging.h
index 0022482..2b714b3 100644
--- a/src/logging.h
+++ b/src/logging.h
@@ -19,7 +19,7 @@
 
 #define INIT_LOGGING(val)
 
-#define VLOG(verboselevel) FX_VLOGST(verboselevel, "core")
+#define VLOG(verboselevel) ((void)verboselevel); FX_LOGST(DEBUG, "core")
 #define LOG(level) FX_LOGST(level, "core")
 #define LOG_FIRST_N(verboselevel, n) FX_LOGST_FIRST_N(verboselevel, n, "core")