util: sock_l4() determine protocol from epoll type rather than the reverse

sock_l4() creates a socket of the given IP protocol number, and adds it to
the epoll state.  Currently it determines the correct tag for the epoll
data based on the protocol.  However, we have some future cases where we
might want different semantics, and therefore epoll types, for sockets of
the same protocol.  So, change sock_l4() to take the epoll type as an
explicit parameter, and determine the protocol from that.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

util.h

@@ -137,13 +137,14 @@ int do_clone(int (*fn)(void *), char *stack_area, size_t stack_size, int flags,
 #include <limits.h>
 #include <stdint.h>
 
+#include "epoll_type.h"
 #include "packet.h"
 
 struct ctx;
 
 /* cppcheck-suppress funcArgNamesDifferent */
 __attribute__ ((weak)) int ffsl(long int i) { return __builtin_ffsl(i); }
-int sock_l4(const struct ctx *c, sa_family_t af, uint8_t proto,
+int sock_l4(const struct ctx *c, sa_family_t af, enum epoll_type type,
 	    const void *bind_addr, const char *ifname, uint16_t port,
 	    uint32_t data);
 void sock_probe_mem(struct ctx *c);