coresight: etm-perf: Fix define build issue when built as module

CONFIG_CORESIGHT_SOURCE_ETM4X is undefined when built as module,
CONFIG_CORESIGHT_SOURCE_ETM4X_MODULE is defined instead.

Therefore code in format_attr_contextid_show() not correctly complied
when coresight built as module.

Use IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X) to correct this.

Link: https://lore.kernel.org/r/20210414194808.22872-1-mike.leach@linaro.org
Fixes: 88f11864 ("coresight: etm-perf: Support PID tracing for kernel at EL2")
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210415202404.945368-2-mathieu.poirier@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing/coresight/coresight-etm-perf.c

@@ -52,7 +52,7 @@ static ssize_t format_attr_contextid_show(struct device *dev,
 {
 	int pid_fmt = ETM_OPT_CTXTID;
 
-#if defined(CONFIG_CORESIGHT_SOURCE_ETM4X)
+#if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X)
 	pid_fmt = is_kernel_in_hyp_mode() ? ETM_OPT_CTXTID2 : ETM_OPT_CTXTID;
 #endif
 	return sprintf(page, "config:%d\n", pid_fmt);