binary module build: use kernel headers from highest version

Instead of uname -a, which might return a kernel version for which
there are no headers installed (eg: chroot build), use the highest
version of kernel headers actually available

Change-Id: I8f188e89c71a37e5da828bb79df84b676a771bab
Signed-off-by: Luca Boccassi <luca.boccassi@gmail.com>

diff --git a/debian/rules b/debian/rules
index 5899dd0..2d69b82 100755 (executable)
--- a/debian/rules
+++ b/debian/rules
@@ -59,7 +59,7 @@ else
 ifneq (,$(filter ksrc=%,$(DEB_BUILD_OPTIONS)))
     KSRC := $(patsubst ksrc=%,%,$(filter ksrc=%,$(DEB_BUILD_OPTIONS)))
 else
-    KSRC := /lib/modules/$(shell uname -r)/build
+    KSRC := /lib/modules/$(shell LIST=$$(ls /lib/modules/); for dir in $$LIST; do test -d /lib/modules/$$dir/build && echo $$dir; done | sort -V | tail -n1)/build
 endif
 
 KVERS := $(shell perl debian/kernel-version $(KSRC))