ci: Build in debug mode for code coverage analysis

Change-Id: I3312cdf0da0a29638bb0e5223e081a805600ba6c
Refs: #2141
diff --git a/.waf-tools/coverage.py b/.waf-tools/coverage.py
index 8045aa8..ce92883 100644
--- a/.waf-tools/coverage.py
+++ b/.waf-tools/coverage.py
@@ -1,6 +1,6 @@
 # -*- Mode: python; py-indent-offset: 4; indent-tabs-mode: nil; coding: utf-8; -*-
 
-from waflib import TaskGen
+from waflib import TaskGen, Logs
 
 def options(opt):
     opt.add_option('--with-coverage', action='store_true', default=False, dest='with_coverage',
@@ -8,6 +8,8 @@
 
 def configure(conf):
     if conf.options.with_coverage:
+        if not conf.options.debug:
+            conf.fatal("Code coverage flags require debug mode compilation (add --debug)")
         conf.check_cxx(cxxflags=['-fprofile-arcs', '-ftest-coverage', '-fPIC'],
                        linkflags=['-fprofile-arcs'], uselib_store='GCOV', mandatory=True)