[master] 6a3cff82e take 2 on this signedness fix

[Nils Goroll]

commit 6a3cff82e820031604ff9e77f67ad66b2c384b81
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Sat Apr 4 17:24:55 2020 +0200

    take 2 on this signedness fix
    
    sorry, I got the first attempt wrong

diff --git a/lib/libvcc/vcc_acl.c b/lib/libvcc/vcc_acl.c
index 60e4321a4..689455926 100644
--- a/lib/libvcc/vcc_acl.c
+++ b/lib/libvcc/vcc_acl.c
@@ -115,7 +115,7 @@ vcc_acl_chk(struct vcc *tl, const struct acl_e *ae, const int l,
 	assert (ll >= 0);
 	m %= 8;
 
-	if (m && (*p << m & UINT8_C(0xff)) != 0) {
+	if (m && ((unsigned)*p << m & 0xff) != 0) {
 		ret = 1;
 		m = 0xff00 >> m;
 		*p &= m;