sdm845-common: Update kernel target level

Updating kernel target level to Android Q

checkvintf Error
checkvintf E : files are incompatible:
    Runtime info and framework compatibility matrix are
    incompatible: Kernel FCM version is not specified, but kernel version
    4.9.337 is found. Fix by specifying kernel FCM version in device
checkvintf E : manifest. For example, for a *-r kernel:
checkvintf E : <kernel target-level="4"/>
checkvintf E : INCOMPATIBLE

Bug: 148823278
Change-Id: Ia30013045b0fe15abc859dda503aed790aaeeb76

manifest.xml

@@ -26,6 +26,7 @@ OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 -->
 <manifest version="1.0" type="device" target-level="4">
+    <kernel target-level="4"/>
     <hal format="hidl">
         <name>android.hardware.audio</name>
         <transport>hwbinder</transport>