https://dev.gnupg.org/T6442

Patch as suggested by Werned in https://dev.gnupg.org/T6442#169396

--- a/random/rndgetentropy.c
+++ b/random/rndgetentropy.c
@@ -94,8 +94,13 @@
                * and might not be applicable on other FIPS modules not running
                * RHEL kernel.
                */
+#ifdef GRND_RANDOM
               nbytes = length < 32 ? length : 32;
               ret = getrandom (buffer, nbytes, GRND_RANDOM);
+#else
+              ret = -1;
+              gpg_err_set_errno (ENOSYS);
+#endif
             }
           else
             {