flowgrindd: fix compile error in read_data

gcc -DHAVE_CONFIG_H -I. -I..    -Wall -Wextra -Werror=implicit -std=gnu99 -fgnu89-inline  -I/usr/include -I/usr/include  -I/usr/include -g -O2 -MT flowgrindd-daemon.o -MD -MP -MF .deps/flowgrindd-daemon.Tpo -c -o flowgrindd-daemon.o `test -f 'daemon.c' || echo './'`daemon.c
daemon.c: In function 'read_data':
daemon.c:1129:3: error: 'else' without a previous 'if'

gcc-4.7.real (Ubuntu/Linaro 4.7.3-1ubuntu1) 4.7.3
flowgrindd: fix compile error in set_affinity

This patch fixes the following error:
gcc -DHAVE_CONFIG_H -I. -I..    -Wall -Wextra -Werror=implicit -std=gnu99 -fgnu89-inline  -I/usr/include -I/usr/include  -I/usr/include -g -O2 -MT flowgrindd-flowgrindd.o -MD -MP -MF .deps/flowgrindd-flowgrindd.Tpo -c -o flowgrindd-flowgrindd.o `test -f 'flowgrindd.c' || echo './'`flowgrindd.c
flowgrindd.c: In function 'set_affinity':
flowgrindd.c:973:3: error: expected ')' before 'progname'
flowgrindd.c:973:3: warning: format '%s' expects a matching 'char *' argument [-Wformat]
flowgrindd.c:973:3: warning: format '%s' expects a matching 'char *' argument [-Wformat]
flowgrindd.c:973:3: warning: format '%d' expects a matching 'int' argument [-Wformat]
flowgrindd.c:973:3: warning: format '%d' expects a matching 'int' argument [-Wformat]
flowgrindd.c:973:3: warning: format '%d' expects a matching 'int' argument [-Wformat]
flowgrindd.c:973:3: warning: format '%s' expects a matching 'char *' argument [-Wformat]
flowgrindd.c:973:3: warning: format '%d' expects a matching 'int' argument [-Wformat]
flowgrindd.c:973:3: warning: format '%i' expects a matching 'int' argument [-Wformat]
flowgrindd: more diligent flow initialization

Closes LP#1237447:
"flowgrindd crashes in a 'non-allowed' cong module as SO is set in a second run"
make-version: DRYify in anticipation of better gitversion.h handling.
make-version: use `cmp` to conditionally overwrite gitversion.h
Merge pull request #9 from mmlb/master

Update gitversion.h only when necessary.