debug-info-defconfig: add debug symbols needed by pahole

With this we can see the structures

pahole -C 'snd_sof_dev' sound/soc/sof/snd-sof.o
struct snd_sof_dev {
	struct device *            dev;                  /*     0     8 */
	spinlock_t                 ipc_lock;             /*     8    72 */
	/* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */
	spinlock_t                 hw_lock;              /*    80    72 */
	/* --- cacheline 2 boundary (128 bytes) was 24 bytes ago --- */
	bool                       dspless_mode_selected; /*   152     1 */

	/* XXX 7 bytes hole, try to pack */

	struct sof_firmware        basefw;               /*   160    16 */

	/* XXX last struct has 4 bytes of padding */

	struct snd_soc_component_driver plat_drv;        /*   176   384 */
...

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>

debug-info-defconfig

@@ -0,0 +1,3 @@
+CONFIG_DEBUG_INFO=y
+CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
+CONFIG_DEBUG_INFO_BTF=y

kconfig-sof-default.sh

@@ -22,4 +22,5 @@ $COMMAND .config \
 	 "$KCONFIG_DIR"/soundwire-defconfig \
 	 "$KCONFIG_DIR"/soundwire-codecs-defconfig \
 	 "$KCONFIG_DIR"/bpf-defconfig \
+	 "$KCONFIG_DIR"/debug-info-defconfig \
 	 "$@"