linux-qcom-6.18: conditionally include qcom_debug.config for aarch64 debug builds

Include `qcom_debug.config` in KBUILD_CONFIG_EXTRA for aarch64 only when
`DEBUG_BUILD` is enabled. This enables QCOM-specific debug options such as
DCC and memory dump support for debug builds, while leaving normal builds
unaffected.

Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>

Author: jiegan0107

recipes-kernel/linux/linux-qcom_6.18.bb

@@ -43,6 +43,7 @@ KBUILD_CONFIG_EXTRA = "${@bb.utils.contains('DISTRO_FEATURES', 'hardened', '${S}
 KBUILD_CONFIG_EXTRA:append:aarch64 = " ${S}/arch/arm64/configs/prune.config"
 KBUILD_CONFIG_EXTRA:append:aarch64 = " ${S}/arch/arm64/configs/qcom.config"
 KBUILD_CONFIG_EXTRA:append = " ${@oe.utils.vartrue('DEBUG_BUILD', '${S}/kernel/configs/debug.config', '', d)}"
+KBUILD_CONFIG_EXTRA:append:aarch64 = " ${@oe.utils.vartrue('DEBUG_BUILD', '${S}/arch/arm64/configs/qcom_debug.config', '', d)}"
 
 do_configure:prepend() {
     # Use a copy of the 'defconfig' from the actual repo to merge fragments