tests: sgsn_test: Define wrap APIs with correct parameters

Fixes following compilation warnings:

osmo-sgsn/tests/sgsn/sgsn_test.c: In function ‘test_gmm_attach_subscr’:
osmo-sgsn/tests/sgsn/sgsn_test.c:1110:30: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
  subscr_request_auth_info_cb = my_subscr_request_auth_info;
                              ^
osmo-sgsn/tests/sgsn/sgsn_test.c: In function ‘test_gmm_attach_subscr_fake_auth’:
osmo-sgsn/tests/sgsn/sgsn_test.c:1144:30: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
  subscr_request_auth_info_cb = my_subscr_request_auth_info_fake_auth;
                              ^
osmo-sgsn/tests/sgsn/sgsn_test.c: In function ‘test_gmm_attach_subscr_gsup_auth’:
osmo-sgsn/tests/sgsn/sgsn_test.c:1275:30: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
  subscr_request_auth_info_cb = my_subscr_request_auth_info_gsup_auth;
                              ^

Change-Id: I5fcb3d460d8becb4cc917fc8d27bfc7e49d50b90
1 file changed