Fix klocwork issues

Klockwork reports these issues:
1. phosphor-watchdog/src/mainapp.cpp:119 | main()
   'fallbackAlways' is used uninitialized in this function.
2. phosphor-watchdog/src/mainapp.cpp:129 | main()
   'watchPostcodes' is used uninitialized in this function.
3. phosphor-watchdog/src/mainapp.cpp:80 | main()
   'continueAfterTimeout' is used uninitialized in this function.

This commit adds default values to resolve these issues.

Tested: Watchdog service worked well.

Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Change-Id: Ib88afb60e801c3f90e039cca99dca5409e896fc1
1 file changed