std.Target: Fix getVersionRangeTag() for bridgeos.

Until we actually figure out a version range for this, we shouldn't classify
this as using semver. Doing so results in a panic when trying to access the
version range since it's not in fact a semver value.

lib/std/Target.zig

@@ -189,7 +189,9 @@ pub const Os = struct {
                 .other,
                 => .none,
 
-                .bridgeos,
+                // This should use semver once we determine the version history.
+                .bridgeos => .none,
+
                 .driverkit,
                 .freebsd,
                 .macos,