dlmisc.c: fix uclibc build

[GitHub pull_request - opened]

alsa-project/alsa-lib pull request #58 was opened from bkuhls:

RTLD_DL_LINKMAP & RTLD_DI_ORIGIN, are unsupported on uClibc:
https://cgit.uclibc-ng.org/cgi/cgit/uclibc-ng.git/tree/include/dlfcn.h#n106

This patch adds detection for uClibc because uClibc also defines
__GLIBC__:
https://lists.gnu.org/archive/html/bug-gnulib/2010-11/msg00280.html

Request URL   : https://github.com/alsa-project/alsa-lib/pull/58
Patch URL     : https://github.com/alsa-project/alsa-lib/pull/58.patch
Repository URL: https://github.com/alsa-project/alsa-lib