tpm/tpm-sysfs: active_show() can be static

so we make it static

CC: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
CC: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index c3503cb..01730a2 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -148,7 +148,7 @@
 }
 static DEVICE_ATTR_RO(enabled);
 
-ssize_t active_show(struct device *dev, struct device_attribute *attr,
+static ssize_t active_show(struct device *dev, struct device_attribute *attr,
 		    char *buf)
 {
 	cap_t cap;