meson: Fix targetos match for illumos and Solaris.

qemu 8.1.0 breaks on illumos platforms due to _XOPEN_SOURCE and others no longer being set correctly, leading to breakage such as:

  https://us-central.manta.mnx.io/pkgsrc/public/reports/trunk/tools/20230908.1404/qemu-8.1.0/build.log

This is a result of meson conversion which incorrectly matches against 'solaris' instead of 'sunos' for uname.

First time submitting a patch here, hope I did it correctly.  Thanks.

Signed-off-by: Jonathan Perkin <jonathan@perkin.org.uk>
Message-ID: <ZPtdxtum9UVPy58J@perkin.org.uk>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit fb0a8b0)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
(Mjt: omit net/meson.build change before v8.1.0-279-g73258b3864, adjust context befor v8.1.0-288-g2fc36530de)

meson.build

@@ -225,7 +225,7 @@ if targetos == 'darwin'
   # Disable attempts to use ObjectiveC features in os/object.h since they
   # won't work when we're compiling with gcc as a C compiler.
   qemu_common_flags += '-DOS_OBJECT_USE_OBJC=0'
-elif targetos == 'solaris'
+elif targetos == 'sunos'
   # needed for CMSG_ macros in sys/socket.h
   qemu_common_flags += '-D_XOPEN_SOURCE=600'
   # needed for TIOCWIN* defines in termios.h
@@ -2056,7 +2056,7 @@ have_slirp_smbd = get_option('slirp_smbd') \
 if have_slirp_smbd
   smbd_path = get_option('smbd')
   if smbd_path == ''
-    smbd_path = (targetos == 'solaris' ? '/usr/sfw/sbin/smbd' : '/usr/sbin/smbd')
+    smbd_path = (targetos == 'sunos' ? '/usr/sfw/sbin/smbd' : '/usr/sbin/smbd')
   endif
   config_host_data.set_quoted('CONFIG_SMBD_COMMAND', smbd_path)
 endif