[glibc/maskray/relr] elf: Fix e6fd79f379 build with --enable-tunables=no

[glibc/maskray/relr] elf: Fix e6fd79f379 build with --enable-tunables=no

[Fangrui Song]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=927246e1882e4aa0ac3abac1fc795be494c38141

commit 927246e1882e4aa0ac3abac1fc795be494c38141
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Thu Oct 21 17:26:32 2021 -0300

    elf: Fix e6fd79f379 build with --enable-tunables=no
    
    The _dl_sort_maps_init() is not defined when tunables is not enabled.
    
    Checked on x86_64-linux-gnu.

Diff:
---
 sysdeps/generic/ldsodefs.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index 65a6a51633..1318c36dce 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -1245,7 +1245,16 @@ extern struct link_map * _dl_get_dl_main_map (void)
 #endif
 
 /* Initialize the DSO sort algorithm to use.  */
+#if !HAVE_TUNABLES
+static inline void
+__always_inline
+_dl_sort_maps_init (void)
+{
+  /* This is optimized out if tunables are not enabled.  */
+}
+#else
 extern void _dl_sort_maps_init (void) attribute_hidden;
+#endif
 
 /* Initialization of libpthread for statically linked applications.
    If libpthread is not linked in, this is an empty function.  */