rpmsg: char: Remove useless include

No facility requests the include of rpmsg_internal.h header file.

Signed-off-by: Arnaud Pouliquen <[e-mail]>
Reviewed-by: Mathieu Poirier <[e-mail]>
Signed-off-by: Bjorn Andersson <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/rpmsg/rpmsg_char.c

···
 #include <linux/uaccess.h>
 #include <uapi/linux/rpmsg.h>
 
-#include "rpmsg_internal.h"
-
 #define RPMSG_DEV_MAX	(MINORMASK + 1)
 
 static dev_t rpmsg_major;