zephyr: remove infinite recursion on Broadwell

Broadwell support with Zephyr had only been dry-coded, it has never
been tested, and it contains an infinite recursion bug: functions
platform_timer_get() and arch_timer_get_system() call each other
infinitely. Break the recursion formally, until a proper fix is
available.

Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>

Author: lyakh

zephyr/wrapper.c

@@ -281,7 +281,8 @@ uint64_t platform_timer_get(struct timer *timer)
 
 	return time;
 #elif defined(CONFIG_SOC_SERIES_INTEL_ADSP_BROADWELL)
-	return arch_timer_get_system(timer);
+	// FIXME!
+	return 0;
 #else
 	/* CAVS versions */
 	return shim_read64(SHIM_DSPWC);