build/ops: do_cmake.sh: get rid of which dependency

"which" is not available on minimal systems, whereas "type" is a shell builtin,
so the chances of the command "just working" are greater with type than with
which.

In other parts of Ceph build/ops we have replaced "which" with "type" to good
effect.

Signed-off-by: Nathan Cutler <ncutler@suse.com>

do_cmake.sh

@@ -5,7 +5,7 @@ if test -e build; then
     exit 1
 fi
 
-if which ccache ; then
+if type ccache > /dev/null 2>&1 ; then
     echo "enabling ccache"
     ARGS="$ARGS -DWITH_CCACHE=ON"
 fi