Cirrus CI: Add the libssl-dev package in the Linux task

(cherry picked from commit b5fa3912c0ea8d1409993fdaca95aa95924eb2f2)
diff --git a/.cirrus.yml b/.cirrus.yml
index 4ceb54d..8c82a3e 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -34,7 +34,7 @@
     MAKEFLAGS: -j 3
   script:
     - apt-get -qy update >/dev/null
-    - apt-get -qy install libdbus-1-dev libbluetooth-dev libnl-genl-3-dev libibverbs-dev >/dev/null
+    - apt-get -qy install libdbus-1-dev libbluetooth-dev libnl-genl-3-dev libibverbs-dev libssl-dev >/dev/null
     - apt-get -qy install flex bison autoconf make clang gcc valgrind >/dev/null
     - apt-get -qy install cmake git bc >/dev/null # for build_matrix.sh and build.sh
     - apt list --installed 'lib*-dev'