rename __getgrent so that it doesn't conflict with some libc's
diff --git a/libpwdgrp/grent.c b/libpwdgrp/grent.c
index 609ed1a..ff3c49e 100644
--- a/libpwdgrp/grent.c
+++ b/libpwdgrp/grent.c
@@ -50,5 +50,5 @@
 {
 	if (grp_fd == -1)
 		return NULL;
-	return __getgrent(grp_fd);
+	return bb_getgrent(grp_fd);
 }