configure: detect asprintf/vasprintf the standard way

The mingw-w64 variant is equivalent to ours. No need to do a special case.
These are GNU functions, not C11 or POSIX functions.

configure.ac

@@ -753,7 +753,7 @@ need_libc=false
 
 dnl Check for usual libc functions
 AC_CHECK_FUNCS([accept4 dup3 fcntl flock fstatat fstatvfs fork getmntent_r getenv getpwuid_r isatty memalign mkostemp mmap open_memstream newlocale pipe2 posix_fadvise setlocale stricmp uselocale wordexp])
-AC_REPLACE_FUNCS([aligned_alloc atof atoll dirfd fdopendir flockfile fsync getdelim getpid gmtime_r lfind lldiv localtime_r memrchr nrand48 poll posix_memalign readv recvmsg rewind sendmsg setenv strcasecmp strcasestr strdup strlcpy strndup strnlen strnstr strsep strtof strtok_r strtoll swab tdestroy tfind timegm timespec_get strverscmp writev])
+AC_REPLACE_FUNCS([aligned_alloc asprintf atof atoll dirfd fdopendir flockfile fsync getdelim getpid gmtime_r lfind lldiv localtime_r memrchr nrand48 poll posix_memalign readv recvmsg rewind sendmsg setenv strcasecmp strcasestr strdup strlcpy strndup strnlen strnstr strsep strtof strtok_r strtoll swab tdestroy tfind timegm timespec_get strverscmp vasprintf writev])
 AC_REPLACE_FUNCS([gettimeofday])
 AC_CHECK_FUNC(fdatasync,,
   [AC_DEFINE(fdatasync, fsync, [Alias fdatasync() to fsync() if missing.])
@@ -761,10 +761,6 @@ AC_CHECK_FUNC(fdatasync,,
 
 VLC_REPLACE_DECL([realpath], [#include <stdlib.h>])
 
-dnl mingw64 implements those as static inline, not functions with C linkage
-VLC_REPLACE_DECL([asprintf], [#include <stdio.h>])
-VLC_REPLACE_DECL([vasprintf], [#include <stdio.h>])
-
 # Windows CE does not have strcoll()
 AC_FUNC_STRCOLL
 

meson.build

@@ -635,6 +635,8 @@ libcompat_functions = [
     ['localtime_r',      '#include <time.h>'],
     ['strverscmp',       '#include <string.h>'],
     ['writev',           '#include <sys/uio.h>'],
+    ['asprintf',         '#include <stdio.h>'],
+    ['vasprintf',        '#include <stdio.h>'],
 
     ['gettimeofday',     '#include <sys/time.h>'],
 
@@ -669,11 +671,8 @@ foreach f : libcompat_functions
 endforeach
 
 # These functions need to be checked with has_header_symbol as
-# MinGW-w64 implements those as static inline, not functions with C linkage
 libcompat_functions = [
     ['realpath',         'stdlib.h'],
-    ['asprintf',         'stdio.h'],
-    ['vasprintf',        'stdio.h'],
 ]
 
 foreach f : libcompat_functions