Fix build with LibreSSL:

./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_meth_set_read'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_get_data'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_meth_set_write'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_meth_set_ctrl'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_meth_set_puts'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_meth_free'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_meth_new'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_set_init'
./.libs/libspice-client-glib-2.0.so: undefined reference to `EVP_PKEY_get0_RSA'
./.libs/libspice-client-glib-2.0.so: undefined reference to `ASN1_STRING_get0_data'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_get_new_index'
./.libs/libspice-client-glib-2.0.so: undefined reference to `BIO_set_data'
cc: error: linker command failed with exit code 1 (use -v to see invocation)

Patches were submitted and accepted by upstream:

https://lists.freedesktop.org/archives/spice-commits/2018-January/004276.html
https://lists.freedesktop.org/archives/spice-commits/2018-January/004277.html

PR: 225407
Submitted by: myself
Approved by: maintainer timeout