linux: fix perf build with older kernels

Signed-off-by: Stephan Raue <stephan@openelec.tv>

packages/linux/package.mk

@@ -142,6 +142,7 @@ make_target() {
     ( cd tools/perf
 
       # dont use some optimizations because of build problems
+        strip_lto
         LDFLAGS=`echo $LDFLAGS | sed -e "s|-Wl,--as-needed||"`
 
       export FLAGSGLIBC="$CFLAGS -I$SYSROOT_PREFIX/usr/include"
@@ -160,6 +161,7 @@ make_target() {
            PYTHON=$SYSROOT_PREFIX/usr/bin/python \
            WERROR=0 \
            NO_SLANG=1 \
+           EXTRA_CFLAGS="$CFLAGS"
     )
   fi
 }