Update a couple of our m4 files for autoconf
diff --git a/aclocal/ax_boost_base.m4 b/aclocal/ax_boost_base.m4
index 19c71b6..d540395 100644
--- a/aclocal/ax_boost_base.m4
+++ b/aclocal/ax_boost_base.m4
@@ -33,7 +33,7 @@
 #   and this notice are preserved. This file is offered as-is, without any
 #   warranty.
 
-#serial 42
+#serial 45
 
 # example boost program (need to pass version)
 m4_define([_AX_BOOST_BASE_PROGRAM],
@@ -113,8 +113,8 @@
     dnl are found, e.g. when only header-only libraries are installed!
     AS_CASE([${host_cpu}],
       [x86_64],[libsubdirs="lib64 libx32 lib lib64"],
-      [ppc64|s390x|sparc64|aarch64|ppc64le],[libsubdirs="lib64 lib lib64"],
-      [libsubdirs="lib"],
+      [ppc64|powerpc64|s390x|sparc64|aarch64|ppc64le|powerpc64le|riscv64],[libsubdirs="lib64 lib lib64"],
+      [libsubdirs="lib"]
     )
 
     dnl allow for real multi-arch paths e.g. /usr/lib/x86_64-linux-gnu. Give