Enable verbose dnssec-keygen output in the "mkeys" system test

dnssec-keygen invocations which are part of the "mkeys" system test
sometimes fail in CI with the following error messages:

    dnssec-keygen: warning: RSA_generate_key_ex failed (crypto failure)
    dnssec-keygen: fatal: failed to generate key ./RSASHA1: crypto failure

Since the aforementioned invocations of dnssec-keygen do not include the
"-v1" command line switch, detailed OpenSSL error logging is suppressed,
hindering efforts to troubleshoot these failures.  Add "-v1" to all
dnssec-keygen command lines in the "mkeys" system test, hoping this will
help uncover the reason for its intermittent failures.
25 jobs for 477-enable-verbose-dnssec-keygen-output-in-the-mkeys-system-test in 8 minutes and 14 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Precheck
passed #36932
amd64 docker linux
precheck:debian:sid:amd64

00:00:11

 
  Build
passed #36933
amd64 docker linux
build:centos:centos6:amd64

00:02:38

passed #36934
amd64 docker linux
build:centos:centos7:amd64

00:02:50

passed #36935
amd64 docker linux
build:clang:debian:stretch:amd64

00:03:05

passed #36939
i386 docker linux
build:clang:debian:stretch:i386

00:01:49

passed #36936
amd64 docker linux
build:debian:jessie:amd64

00:01:25

passed #36938
amd64 docker linux
build:debian:sid:amd64

00:01:39

passed #36940
i386 docker linux
build:debian:sid:i386

00:01:44

passed #36937
amd64 docker linux
build:debian:stretch:amd64

00:03:06

passed #36941
amd64 docker linux
pkcs11:build:debian:sid:amd64

00:01:35

 
  Test
passed #36956
amd64 docker linux
pkcs11:systemtest:debian:sid:amd64

00:04:49

passed #36955
amd64 docker linux
pkcs11:unittest:debian:sid:amd64

00:00:44

passed #36949
amd64 docker linux
systemtest:centos:centos6:amd64

00:04:37

passed #36950
amd64 docker linux
systemtest:centos:centos7:amd64

00:04:36

passed #36951
amd64 docker linux
systemtest:debian:jessie:amd64

00:04:40

passed #36953
amd64 docker linux
systemtest:debian:sid:amd64

00:04:38

passed #36954
i386 docker linux
systemtest:debian:sid:i386

00:04:49

passed #36952
amd64 docker linux
systemtest:debian:stretch:amd64

00:04:51

passed #36942
amd64 docker linux
unittest:centos:centos6:amd64

00:00:58

passed #36943
amd64 docker linux
unittest:centos:centos7:amd64

00:00:51

passed #36947
amd64 docker linux
unittest:clang:debian:stretch:amd64

00:00:46

passed #36944
amd64 docker linux
unittest:debian:jessie:amd64

00:00:58

passed #36946
amd64 docker linux
unittest:debian:sid:amd64

00:00:49

passed #36948
i386 docker linux
unittest:debian:sid:i386

00:00:43

passed #36945
amd64 docker linux
unittest:debian:stretch:amd64

00:00:52