rrdtool: Update tp 1.9.0

rrdtool: Update tp 1.9.0

For details see:
https://github.com/oetiker/rrdtool-1.x/releases/tag/v1.9.0

"RRDtool 1.9.0 — 2024-07-29
Bugfixes

    Fix ytop and ybase adjustments for overlaping area issue on transparent areas @turban
    Suppress warnings of implicit fall through @youpong
    Update tarball download link in doc @c72578
    Fix unsigned integer overflow in rrdtool first. Add test for rrd_first() @c72578
    Fix tests under MSYS2 (Windows) @c72578
    Fix BUILD_DATE in rrdtool help output @c72578
    acinclude.m4: Include <stdlib.h> when using exit @ryandesign
    rrdtool-release: Create NUMVERS from VERSION file @c72578
    Avoids leaking of file descriptors in multi threaded programs by @ensc
    Avoids potential unterminated string because of fixed PATH_MAX buffer
    Fix extra reference of parameters of rrd_fetch_dbi_{long,double} @jamborm"

Signed-off-by: Matthias Fischer <matthias.fischer@ipfire.org>