Patch to set correct compiler flags for 'armflang' on 'aarch64'

Dear libtool-patches,

On Linux on 'aarch64' using the 'armflang' compiler I got the following 
error:

   FCLD     src/libqmckl.la
clang-13: error: unknown argument: '-soname'
clang-13: error: no such file or directory: 'libqmckl.so.0'
make[2]: *** [Makefile:1203: src/libqmckl.la] Error 1
make[2]: Leaving directory '/users/m23005/scemama/qmckl'
make[1]: *** [Makefile:1520: all-recursive] Error 1
make[1]: Leaving directory '/users/m23005/scemama/qmckl'
make: *** [Makefile:1046: all] Error 2

John C. Linford <[email protected]> from ARM suggested the following 
workaround for end users:

$ ./configure ...
$ sed -i -e 's#wl=""#wl="-Wl,"#g' libtool
$ sed -i -e 's#pic_flag=""#pic_flag=" -fPIC -DPIC"#g' libtool
$ make

This works, so I patched the 'libtool.m4' file to include  the correct 
flags for the 'armflang' compiler:

$ git format-patch --stdout origin/master

 From 3657095457c4a311f3e775c6267b11c575e7c245 Mon Sep 17 00:00:00 2001
From: Francois Coppens <[email protected]>
Date: Fri, 10 Feb 2023 15:36:16 +0100
Subject: [PATCH] armflang patch
---
  m4/libtool.m4 | 6 ++++++
  1 file changed, 6 insertions(+)
diff --git a/m4/libtool.m4 b/m4/libtool.m4
index 79a2451e..df1a7860 100644
--- a/m4/libtool.m4
+++ b/m4/libtool.m4
@@ -4719,6 +4719,12 @@ m4_if([$1], [CXX], [
         _LT_TAGVAR(lt_prog_compiler_pic, $1)='-fPIC'P
         _LT_TAGVAR(lt_prog_compiler_static, $1)='-static'
          ;;
+      # ARM flang
+      armflang*)
+        _LT_TAGVAR(lt_prog_compiler_wl, $1)='-Wl,'
+        _LT_TAGVAR(lt_prog_compiler_pic, $1)='-fPIC'
+        _LT_TAGVAR(lt_prog_compiler_static, $1)='-static
+        ;;
        # Lahey Fortran 8.1.
        lf95*)
         _LT_TAGVAR(lt_prog_compiler_wl, $1)='-Wl,'


This works as well and the end user does no longer have to use the 
proposed workaround.

I remain at your disposal for more inforation if needed.

With kind regards,
Francois Coppens