trace: do not set trace_ctx section for Zephyr [REVERTME]

This section is generating warnings when build with Zephyr, so remove
for now.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

Author: nashif

src/include/sof/trace/trace.h

@@ -296,7 +296,7 @@ struct tr_ctx {
 	uint32_t level;				/**< Default log level */
 };
 
-#if defined(UNIT_TEST)
+#if defined(UNIT_TEST) || defined(__ZEPHYR__)
 #define TRACE_CONTEXT_SECTION
 #else
 #define TRACE_CONTEXT_SECTION __section(".trace_ctx")