pwritev/pwritev01.c: add new testcase

Test pwritev(2) with some basic functions.
Pwritev(2) should succeed to write the expected content of data and
the file offset is not changed after writing the file.

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
diff --git a/configure.ac b/configure.ac
index 609de8f..cc50397 100644
--- a/configure.ac
+++ b/configure.ac
@@ -182,5 +182,6 @@
 LTP_CHECK_KCMP
 LTP_CHECK_KCMP_TYPE
 LTP_CHECK_PREADV
+LTP_CHECK_PWRITEV
 
 AC_OUTPUT