update ax_boost_base.m4 from http://www.gnu.org/software/autoconf-archive/ for adding loongarch information
diff --git a/aclocal/ax_boost_base.m4 b/aclocal/ax_boost_base.m4
index d540395..4065af0 100644
--- a/aclocal/ax_boost_base.m4
+++ b/aclocal/ax_boost_base.m4
@@ -113,7 +113,7 @@
dnl are found, e.g. when only header-only libraries are installed!
AS_CASE([${host_cpu}],
[x86_64],[libsubdirs="lib64 libx32 lib lib64"],
- [ppc64|powerpc64|s390x|sparc64|aarch64|ppc64le|powerpc64le|riscv64],[libsubdirs="lib64 lib lib64"],
+ [ppc64|powerpc64|s390x|sparc64|aarch64|ppc64le|powerpc64le|riscv64|loongarch64],[libsubdirs="lib64 lib lib64"],
[libsubdirs="lib"]
)