turnip: Only link libdrm in the DRM case, not KGSL.

libvulkan's not a fan of opening my libdrm.so.2 from /vendor/lib64 or
/vendor/lib64/hw, but then we shouldn't need it, anyway.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6821>

src/freedreno/vulkan/meson.build

@@ -111,6 +111,7 @@ if with_freedreno_kgsl
   libtu_files += files('tu_kgsl.c')
 else
   libtu_files += files('tu_drm.c')
+  tu_deps += dep_libdrm
 endif
 
 libvulkan_freedreno = shared_library(
@@ -136,7 +137,6 @@ libvulkan_freedreno = shared_library(
     idep_libfreedreno_common,
     dep_dl,
     dep_elf,
-    dep_libdrm,
     dep_m,
     dep_thread,
     dep_valgrind,