UCM: Fix getting previous symbol value on ARM.
UCM: Fix getting previous symbol value on ARM.

 On ARM machine, dlsym(RTLD_DEFAULT) points to a proxy function, and
therefore comparing it to our replacement does not give real indication
on whether we already patched the .got or not. Therefore we use a
different strategy - first try dlsym(RTLD_NEXT) and if it's NULL, revert
to dlsym(RTLD_DEFAULT).

shssf/ucx,sergsagal1/ucx_rocm,abouteiller/ucx,shssf/ucx,sergsagal1/ucx_rocm,abouteiller/ucx,abouteiller/ucx,shssf/ucx,abouteiller/ucx,sergsagal1/ucx_rocm