Staging: bcm: Fix a coding style error reported by checkpatch.pl

Tool checkpatch.pl reported the following error: extern struct class *bcm_class;"
declaration not allowed in .c files. Therefore, I move this declaration into
the header "headers.h" file.
Signed-off-by: Kevin McKinney <klmckinney1@gmail.com>
Reviewed-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/bcm/Bcmchar.c

@@ -1974,8 +1974,6 @@ static const struct file_operations bcm_fops = {
 	.llseek = no_llseek,
 };
 
-extern struct class *bcm_class;
-
 int register_control_device_interface(PMINI_ADAPTER Adapter)
 {
 

drivers/staging/bcm/headers.h

@@ -74,4 +74,6 @@
 #define DRV_VERSION	VER_FILEVERSION_STR
 #define PFX		DRV_NAME " "
 
+extern struct class *bcm_class;
+
 #endif