soletta/soletta_dev_app.py: fix the issue on build #423
soletta/soletta_dev_app.py: fix the issue on build #423

In the build 423, the "ps" command does not support option "-ef".
So the soletta_dev_app auto cases are FAIL.
Submit patch to change the ps usage in code.

Signed-off-by: Lei Yang <884188bc707cc1be54d02b83a73b4695f136ccae@intel.com>

daweiwu/meta-iotqa-1,wanghongjuan/meta-iotqa-1,daweiwu/meta-iotqa-1,ostroproject/meta-iotqa,daweiwu/meta-iotqa-1,ostroproject/meta-iotqa,wanghongjuan/meta-iotqa-1,wanghongjuan/meta-iotqa-1,wanghongjuan/meta-iotqa-1,wanghongjuan/meta-iotqa-1,daweiwu/meta-iotqa-1,daweiwu/meta-iotqa-1,ostroproject/meta-iotqa,ostroproject/meta-iotqa,ostroproject/meta-iotqa