[Mellanox] Use Debian reboot in Nvidia platform reboot when it is invoked from kdump capture boot (#15701) (#16050)

device/mellanox/x86_64-mlnx_msn2700-r0/platform_reboot

@@ -21,13 +21,24 @@ function ParseArguments() {
 }
 
 function SafePwrCycle() {
-    sync ; sync
-    umount -fa > /dev/null 2&>1
+    sync; sync
+    umount -fa > /dev/null 2>&1
     echo 1 > $SYSFS_PWR_CYCLE
 }
 
 ParseArguments "$@"
 
+# Reboot immediately if the kdump capture kernel is running
+VMCORE_FILE=/proc/vmcore
+if [ -s $VMCORE_FILE ]; then
+    sync; sync
+    umount -fa > /dev/null 2>&1
+
+    # Run Debian reboot because the platform reboot isn't available
+    /sbin/reboot
+fi
+
+
 ${FW_UPGRADE_SCRIPT} --upgrade --verbose
 EXIT_CODE="$?"
 if [[ "${EXIT_CODE}" != "${EXIT_SUCCESS}" ]]; then