Add 'hw-management-generate-dump.sh' to 'show techsupport' command (#934

)

**- What I did**
Added 'hw-management-generate-dump.sh' to 'generate_dump' script.
this addon will provide new information under the dump folder regarding hw-mgmt.
New information:

- SMBIOS info - version, system info, base board info
- FW info
- hw-management tree (the fs tree under /var/run/hw-management).
- system fs tree contains: block, bus, class, kernel, power etc..
- system interrupts.
- registers status.
- system sensors data.
- system log.
- Linux version and build.
- current processes,'top' output.

**- How to verify it**
run 'show techsupport' command and see the result file under
/var/dump/sonic_dump_'hostname'_'time'/hw-mgmt

Signed-off-by: Shlomi Bitton <shlomibi@mellanox.com>

scripts/generate_dump

@@ -460,6 +460,13 @@ main() {
         fi
     done
 
+    # run 'hw-management-generate-dump.sh' script and save the result file
+    if [ "$asic" = "mellanox" ]; then
+        /usr/bin/hw-management-generate-dump.sh    
+        save_file "/tmp/hw-mgmt-dump*" "hw-mgmt" false
+        rm -f /tmp/hw-mgmt-dump*
+    fi
+
     # clean up working tar dir before compressing
     $RM $V -rf $TARDIR