st/egl: do not link against libloader

st/egl: do not link against libloader

Move the link to the final targets, like any other place in
mesa/gallium. This allows better visibilty and will prevent
us from including the library archive twice.

Resolves multiple definition of `loader_get_pci_id_for_fd'

multiple definition of `loader_get_pci_id_for_fd'

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79263
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79382
Cc: Chia-I Wu <olv@lunarg.com>
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Chia-I Wu <olv@lunarg.com>
Tested-by: Michel Dänzer <michel.daenzer@amd.com>