Fix minor build issue with UnifyFS. (#23709)

This commit updates the UnifyFS package.py script to include a patch
that fixes the build problems on new-ish Linux distributions.

Fixes issue #23292

var/spack/repos/builtin/packages/unifyfs/include-sys-sysmacros.h.patch

@@ -0,0 +1,43 @@
+Commit: ef1b4caa70beb0a7ae03fc0ef1250b80efe33afc
+Date: Fri, 14 May 2021 15:30:09 -0400
+Subject: [PATCH] Include sys/sysmacros.h in testlib.h
+
+In recent Linux systems, major() and minor() are defined in
+sys/sysmacros.h and sys/types.h no longer includes sys/sysmacros.h.  So,
+we need to include sys/sysmacros.h in testlib.h.
+
+Also adds a check for the existence of sys/sysmacros.h in configure.ac.
+
+Include sys/sysmacros.h in testlib.h
+---
+ configure.ac           | 1 +
+ examples/src/testlib.h | 1 +
+ 2 files changed, 2 insertions(+)
+
+diff --git a/configure.ac b/configure.ac
+index 681cdb7..77719eb 100755
+--- a/configure.ac
++++ b/configure.ac
+@@ -65,6 +65,7 @@ AC_CHECK_HEADERS([fcntl.h inttypes.h libgen.h limits.h mntent.h strings.h syslog
+ AC_CHECK_HEADERS([wchar.h wctype.h])
+ AC_CHECK_HEADERS([sys/mount.h sys/socket.h sys/statfs.h sys/time.h])
+ AC_CHECK_HEADERS([arpa/inet.h netdb.h netinet/in.h])
++AC_CHECK_HEADER([sys/sysmacros.h], [], AC_MSG_ERROR([cannot find required header sys/sysmacros.h]))
+ 
+ # Checks for library functions.
+ AC_FUNC_MALLOC
+diff --git a/examples/src/testlib.h b/examples/src/testlib.h
+index 2b0a698..41c9900 100644
+--- a/examples/src/testlib.h
++++ b/examples/src/testlib.h
+@@ -24,6 +24,7 @@
+ #include <sys/time.h>
+ #include <sys/types.h>
+ #include <sys/stat.h>
++#include <sys/sysmacros.h>
+ #include <unistd.h>
+ #include <time.h>
+ #include <mpi.h>
+-- 
+2.25.1
+

var/spack/repos/builtin/packages/unifyfs/package.py

@@ -57,6 +57,7 @@ class Unifyfs(AutotoolsPackage):
     conflicts('%xl',    when='+fortran')
 
     patch('unifyfs-sysio.c.patch', when='@0.9.1')
+    patch('include-sys-sysmacros.h.patch', when='@0.9.1:0.9.2')
 
     # Parallel disabled to prevent tests from being run out-of-order when
     # installed with the --test={root, all} option.