Revert "Skip basename on musl"

This reverts commit a7f189d.

Author: tgross35

libc-test/build.rs

@@ -4741,9 +4741,6 @@ fn test_linux(target: &str) {
             "posix_basename" if gnu => true,
             "gnu_basename" if gnu => true,
 
-            // https://github.com/kraj/musl/commit/725e17ed6dff4d0cd22487bb64470881e86a92e7
-            "basename" if musl => true,
-
             // FIXME(linux): function pointers changed since Ubuntu 23.10
             "strtol" | "strtoll" | "strtoul" | "strtoull" | "fscanf" | "scanf" | "sscanf" => true,