OvmfPkg/EnrollDefaultKeys: remove Red Hat's hard-coded PK/KEK1

OvmfPkg/EnrollDefaultKeys: remove Red Hat's hard-coded PK/KEK1

The certificate

  "Red Hat Secure Boot (PK/KEK key 1)/emailAddress=secalert@redhat.com"
  SHA1: fd:fc:7f:3c:7e:f3:e0:57:76:ad:d7:98:78:21:6c:9b:e0:e1:95:97

is no longer referenced; remove it.

Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Julien Grall <julien.grall@arm.com>
Bugzilla: https://bugzilla.tianocore.org/show_bug.cgi?id=1747
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Gary Lin <glin@suse.com>