trace: select TIMER_EARLY to avoid infinite recursion

When tracing functions is enabled this adds calls to
__cyg_profile_func_enter() and __cyg_profile_func_exit() to the traced
functions.

__cyg_profile_func_enter() and __cyg_profile_func_exit() invoke
timer_get_us() to record the entry and exit time.

initr_dm() will make gd->dm_root = NULL and gd->timer = NULL, so
timer_get_us() -> get_ticks() -> dm_timer_init() will lead to an
indefinite recursion.

So select TIMER_EARLY when tracing got enabled.
Signed-off-by: NPragnesh Patel <pragnesh.patel@sifive.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NRick Chen <rick@andestech.com>

lib/Kconfig

@@ -210,6 +210,7 @@ config BITREVERSE
 config TRACE
 	bool "Support for tracing of function calls and timing"
 	imply CMD_TRACE
+	select TIMER_EARLY
 	help
 	  Enables function tracing within U-Boot. This allows recording of call
 	  traces including timing information. The command can write data to