cpupower: Fix handling of noopt and nostrip build options

The upstream Makefile uses DEBUG to control both stripping of debug
information *and* disabling optimisations.

We want to disable stripping of debug information so that (normally)
dh_strip can move it into a separate package later.  However we also
want to enable optimisations by default.

Therefore:

- Set the STRIP variable (a command prefix) to "true"
- Set the DEBUG variable (a pseudo-boolean) to "true" if and only if
  the "noopt" build option is used

debian/changelog

@@ -17,6 +17,7 @@ linux (4.18~rc7-1~exp1) UNRELEASED; urgency=medium
     - linux-kbuild: Change "#!/usr/bin/env perl" to "#!/usr/bin/perl"
     - Build with KBUILD_VERBOSE=1 by default
     - objtool, usbip: Build with V=1 by default
+  * cpupower: Fix handling of noopt and nostrip build options
 
  -- Uwe Kleine-König <ukleinek@debian.org>  Sat, 21 Jul 2018 16:52:01 +0200
 

debian/rules.d/tools/power/cpupower/Makefile

@@ -2,7 +2,10 @@ include $(top_rulesdir)/Makefile.inc
 
 MAKE_CPUPOWER := $(shell dpkg-buildflags --export=cmdline) $(MAKE) O=$(CURDIR) CPUFREQ_BENCH=false V=true mandir=/usr/share/man
 
-MAKE_CPUPOWER += DEBUG=$(if $(findstring nostrip,$(DEB_BUILD_OPTIONS)),true,)
+MAKE_CPUPOWER += DEBUG=$(if $(filter noopt,$(DEB_BUILD_OPTIONS)),true,)
+
+# Don't strip binaries here; let dh_strip determine what to do
+MAKE_CPUPOWER += STRIP=true
 
 MAKE_CPUPOWER += CROSS='$(CROSS_COMPILE)'