meson: strip rpath from megadrivers

More specifically, use the library file that has been post-processed by Meson
when creating the hardlinks.

Bugs: https://bugs.freedesktop.org/show_bug.cgi?id=108766
Fixes: 3218056e0e "meson: Build i965 and dri stack"
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>

bin/install_megadrivers.py

@@ -49,7 +49,6 @@ def main():
         if os.path.lexists(to):
             os.unlink(to)
         os.makedirs(to)
-    shutil.copy(args.megadriver, master)
 
     for driver in args.drivers:
         abs_driver = os.path.join(to, driver)

src/gallium/targets/dri/meson.build

@@ -60,6 +60,9 @@ libgallium_dri = shared_library(
     driver_tegra, driver_i915, driver_svga, driver_virgl,
     driver_swr, driver_panfrost, driver_iris
   ],
+  # Will be deleted during installation, see install_megadrivers.py
+  install : true,
+  install_dir : dri_drivers_path,
 )
 
 foreach d : [[with_gallium_kmsro, [

src/gallium/targets/va/meson.build

@@ -49,6 +49,7 @@ libva_gallium = shared_library(
     dep_libdrm, dep_thread, driver_r600, driver_radeonsi, driver_nouveau,
   ],
   link_depends : va_link_depends,
+  # Will be deleted during installation, see install_megadrivers.py
   install : true,
   install_dir : va_drivers_path,
 )

src/gallium/targets/vdpau/meson.build

@@ -55,6 +55,9 @@ libvdpau_gallium = shared_library(
   ],
   link_depends : vdpau_link_depends,
   soversion : '@0@.@1@.0'.format(VDPAU_MAJOR, VDPAU_MINOR),
+  # Will be deleted during installation, see install_megadrivers.py
+  install : true,
+  install_dir : vdpau_drivers_path,
 )
 foreach d : [[with_gallium_r300, 'r300'],
              [with_gallium_r600, 'r600'],

src/gallium/targets/xvmc/meson.build

@@ -47,6 +47,9 @@ libxvmc_gallium = shared_library(
   ],
   dependencies : [dep_thread, driver_r600, driver_nouveau],
   link_depends : xvmc_link_depends,
+  # Will be deleted during installation, see install_megadrivers.py
+  install : true,
+  install_dir : xvmc_drivers_path,
 )
 
 foreach d : [[with_gallium_r600, 'r600'], [with_gallium_nouveau, 'nouveau']]

src/mesa/drivers/dri/meson.build

@@ -54,6 +54,9 @@ if dri_drivers != []
       dep_selinux, dep_libdrm, dep_expat, dep_m, dep_thread, dep_dl, idep_nir,
     ],
     link_args : [ld_args_build_id, ld_args_bsymbolic, ld_args_gc_sections],
+    # Will be deleted during installation, see install_megadrivers.py
+    install : true,
+    install_dir : dri_drivers_path,
   )
 
   meson.add_install_script(