Revert "openblas: update to 0.3.19."

Python code built around python3-numpy and python3-scipy (both linked
with openblas) began emitting warnings after the 0.3.19 update:

    /usr/lib/python3.10/concurrent/futures/thread.py:58:
        RuntimeWarning: overflow encountered in multiply
            result = self.fn(*self.args, **self.kwargs)

that broke program behavior in an Azure VM environment using Intel Xeon
Platinum 8272CL CPUs; the problem was not seen on an AMD Ryzen 5 3600 or
an Intel Core i7-9750H. Downgrading openblas while leaving the rest of
the stack untouched eliminates the problem.

Unfortunately, I do not yet have a proof of concept that can be shared
publicly or more detail about the specific failure, but let's revert to
the last known good version until a specific cause can be identified.

This reverts commit 4f34f570ff.

srcpkgs/openblas/template

@@ -1,7 +1,8 @@
 # Template file for 'openblas'
 pkgname=openblas
-version=0.3.19
-revision=1
+reverts="0.3.19_1"
+version=0.3.18
+revision=2
 wrksrc="OpenBLAS-${version}"
 build_style=gnu-makefile
 make_build_args="HOSTCC=gcc USE_OPENMP=1"
@@ -14,7 +15,7 @@ license="BSD-3-Clause"
 homepage="https://www.openblas.net/"
 changelog="https://raw.githubusercontent.com/xianyi/OpenBLAS/v${version}/Changelog.txt"
 distfiles="https://github.com/xianyi/OpenBLAS/archive/v${version}.tar.gz"
-checksum=947f51bfe50c2a0749304fbe373e00e7637600b0a47b78a51382aeb30ca08562
+checksum=1632c1e8cca62d8bed064b37747e331a1796fc46f688626337362bf0d16aeadb
 
 case "$XBPS_TARGET_MACHINE" in
 	ppc64*) ;;