plugins: fix cross-build using LLVM for Windows targets

llvm-dlltool assumes that it's by default targeting the host architecture
it's running on. That assumption doesn't hold true when cross-compiling.

Signed-off-by: Mohamed Mediouni <mohamed@unpredictable.fr>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Tested-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Link: https://lore.kernel.org/qemu-devel/20260210040722.11375-1-mohamed@unpredictable.fr
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>

plugins/meson.build

@@ -41,9 +41,16 @@ if host_os == 'windows'
   # to find missing symbols in current program.
   win32_qemu_plugin_api_link_flags = ['-Lplugins', '-lqemu_plugin_api']
   if meson.get_compiler('c').get_id() == 'clang'
+    if host_machine.cpu() == 'x86_64'
+      dlltool_target = 'i386:x86-64'
+    elif host_machine.cpu() == 'aarch64'
+      dlltool_target = 'arm64'
+    else
+      error('Unknown machine')
+    endif
     # With LLVM/lld, delaylib is specified at link time (-delayload)
     dlltool = find_program('llvm-dlltool', required: true)
-    dlltool_cmd = [dlltool, '-d', '@INPUT@', '-l', '@OUTPUT@', '-D', 'qemu.exe']
+    dlltool_cmd = [dlltool, '-m', dlltool_target,'-d', '@INPUT@', '-l', '@OUTPUT@', '-D', 'qemu.exe']
     win32_qemu_plugin_api_link_flags += ['-Wl,-delayload=qemu.exe']
   else
     # With gcc/ld, delay lib is built with a specific delay parameter.