watchfrr: indent to Linux CodingStyle

watchfrr: indent to Linux CodingStyle

before this patch, watchfrr was using an inconsistent style that matched
neither GNU nor Linux kernel nor BSD style.  Reindent to Linux kernel
style, which should be pretty close to pimd & ldpd.

indent (2.2.11) options used:
 -nbad -bap -nbc -bbo -hnl -br -brs -c33 -cd33 -ncdb -ce -ci4
 -cli0 -d0 -di1 -nfc1 -i8 -ip0 -l80 -lp -npcs -nprs -npsl -sai
 -saf -saw -ncs -nsc -sob -nfca -cp33 -ss -ts8 -il1

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>