amd/drm-shim: export a function that allows to select a different device

To be used by ACO tests. Need to remove gnu_symbol_visibility for
exporting the symbol.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/38536>

src/amd/drm-shim/amdgpu_noop_drm_shim.c

@@ -8,6 +8,7 @@
 #include <string.h>
 #include "amdgpu_devices.h"
 #include "common/amd_family.h"
+#include "drm-shim/amdgpu_noop_drm_shim.h"
 #include "drm-shim/drm_shim.h"
 #include "drm-uapi/amdgpu_drm.h"
 #include "util/log.h"
@@ -199,10 +200,9 @@ static ioctl_fn_t amdgpu_ioctls[] = {
    [DRM_AMDGPU_SCHED] = amdgpu_ioctl_noop,
 };
 
-static void
-amdgpu_select_device()
+void
+drm_shim_amdgpu_select_device(const char *gpu_id)
 {
-   const char *gpu_id = os_get_option("AMDGPU_GPU_ID");
    if (gpu_id) {
       for (uint32_t i = 0; i < num_amdgpu_devices; i++) {
          const struct amdgpu_device *dev = &amdgpu_devices[i];
@@ -224,7 +224,9 @@ amdgpu_select_device()
 void
 drm_shim_driver_init(void)
 {
-   amdgpu_select_device();
+   const char *gpu_id = os_get_option("AMDGPU_GPU_ID");
+
+   drm_shim_amdgpu_select_device(gpu_id);
 
    shim_device.bus_type = DRM_BUS_PCI;
    shim_device.driver_name = "amdgpu";

src/amd/drm-shim/amdgpu_noop_drm_shim.h

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2025 Valve Corporation
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#ifndef AMDGPU_NOOP_DRM_SHIM_H
+#define AMDGPU_NOOP_DRM_SHIM_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void drm_shim_amdgpu_select_device(const char *gpu_id);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/amd/drm-shim/meson.build

@@ -15,7 +15,6 @@ libamdgpu_noop_drm_shim = shared_library(
   ['amdgpu_noop_drm_shim.c', 'amdgpu_devices.c'],
   include_directories: [inc_include, inc_src, inc_amd],
   dependencies: dep_drm_shim,
-  gnu_symbol_visibility : 'hidden',
   install : true,
 )