Fix format specifier for printing size_t on 32bit size_t platforms

Fix format specifier for printing size_t on 32bit size_t platforms

Today even 32 bit platform generally use a 64bit size_t but Android
armeabi-v7a is an expection to that and uses a 32bit size_t. Use
z as correct specifier for a size_t.

Clang complained about this:

warning: format specifies type 'unsigned long' but the
argument has type 'size_t' (aka 'unsigned int') [-Wformat]

Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20220504113158.1051861-1-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg24277.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>