Bug#828245: balsa: FTBFS for me, and the buildds

[Chris West]

Control: severity -1 serious
Control: retitle -1 balsa: FTBFS with openssl 1.1.0

This is failing to build for me still on sid (with libssl-dev):

auth-cram.c: In function ‘hmac_md5’:
auth-cram.c:134:14: error: storage size of ‘ctx’ isn’t known
   EVP_MD_CTX ctx;
              ^~~
Makefile:515: recipe for target 'auth-cram.o' failed

And on the buildds for the transition:
https://release.debian.org/transitions/html/openssl1.0-rm.html

This is a typical error for this openssl version migration:
the structs have become opaque and you must use pointers everywhere.

Going back to "serious" because that's what the other transition
bugs are today, but they were raised with much more notice; maybe
more time can be taken to fix this.

Chris.