selinux: drop cast to same type

Both the lvalue scontextp and rvalue scontext are of the type char*.
Drop the redundant explicit cast not needed since commit 9a59daa03df7
("SELinux: fix sleeping allocation in security_context_to_sid"), where
the type of scontext changed from const char* to char*.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

security/selinux/ss/services.c

@@ -1452,7 +1452,7 @@ static int string_to_context_struct(struct policydb *pol,
 	/* Parse the security context. */
 
 	rc = -EINVAL;
-	scontextp = (char *) scontext;
+	scontextp = scontext;
 
 	/* Extract the user. */
 	p = scontextp;