libv4l: update to 1.20.0

Removed upstreamed patches.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

libs/libv4l/patches/030-getsubopt.patch

@@ -1,34 +0,0 @@
-POSIX says that behavior when subopts list is empty is undefined.
-musl libs will set value to NULL which leads to crash.
-
-Simply avoid getsubopt, since we cannot rely on it.
-
---- a/utils/v4l2-ctl/v4l2-ctl-common.cpp
-+++ b/utils/v4l2-ctl/v4l2-ctl-common.cpp
-@@ -679,16 +679,17 @@ static bool parse_subset(char *optarg)
- 
- static bool parse_next_subopt(char **subs, char **value)
- {
--	static char *const subopts[] = {
--	    NULL
--	};
--	int opt = getsubopt(subs, subopts, value);
-+	char *p = *subs;
-+	*value = *subs;
- 
--	if (opt < 0 || *value)
--		return false;
--	fprintf(stderr, "No value given to suboption <%s>\n",
--			subopts[opt]);
--	return true;
-+	while (*p && *p != ',')
-+		p++;
-+
-+	if (*p)
-+		*p++ = '\0';
-+
-+	*subs = p;
-+	return false;
- }
- 
- void common_cmd(int ch, char *optarg)