Replace another "test" with "expr".

Error message seen on OpenBSD:
===
./configure[16315]: test: >: unexpected operator/operand
===

Another instance of this problem was fixed previously:
https://github.com/isc-projects/kea/pull/25

diff --git a/configure.ac b/configure.ac
index 6989c00bb75ddc963a86dddd68742554858d43cc..562fc1967c021b7d17488b3a19f5b39e01d87940 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -223,7 +223,7 @@ fi
 AC_SUBST(WARNING_GCC_44_STRICT_ALIASING_CFLAG)
 CPPP="$CPP"
 # gcc 5 preprocessor requires -P for checking its output
-if test "$CXX_DUMP_VERSION" \> "5"; then
+if expr "$CXX_DUMP_VERSION" \> "5" > /dev/null; then
        CPPP="$CPP -P"
 fi