make.sh: Add function to determine how many CPU cores the build host has

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

make.sh

@@ -189,10 +189,7 @@ prepareenv() {
     set +h
     LC_ALL=POSIX
     if [ -z $MAKETUNING ]; then
-	CPU_COUNT="$(getconf _NPROCESSORS_ONLN 2>/dev/null)"
-	if [ -z "${CPU_COUNT}" ]; then
-		CPU_COUNT=1
-	fi
+	CPU_COUNT="$(system_processors)"
 
 	MAKETUNING="-j$(( ${CPU_COUNT} * 2 + 1 ))"
     fi

tools/make-functions

@@ -60,6 +60,10 @@ WARN="\\033[1;35m"
 FAIL="\\033[1;31m"
 NORMAL="\\033[0;39m"
 
+system_processors() {
+	getconf _NPROCESSORS_ONLN 2>/dev/null || echo "1"
+}
+
 system_memory() {
 	local key val unit