BUG/MINOR: cfgparse-quic: fix bbr initialization

To support pacing with cubic, a recent change was introduced to render
quic_cc_algo on bind line dynamically allocated, instead of pointing to
a globally defined variable. This allows customization of the algorithm
callbacks per bind line.

This was not correctly used for BBR as it was set to point to the global
quic_cc_algo_bbr. This causes a segfault on haproxy process closing. Fix
this by properly initializing BBR as other algorithms.

This should fix coverity report from github issue #2786.

Author: a-denoyelle

src/cfgparse-quic.c

@@ -151,7 +151,7 @@ static int bind_parse_quic_cc_algo(char **args, int cur_arg, struct proxy *px,
 
 		/* bbr */
 		algo = QUIC_CC_BBR_STR;
-		cc_algo = &quic_cc_algo_bbr;
+		*cc_algo = quic_cc_algo_bbr;
 		arg += strlen(QUIC_CC_BBR_STR);
 	}
 	else if (strncmp(arg, QUIC_CC_NO_CC_STR, strlen(QUIC_CC_NO_CC_STR)) == 0) {