MDEV-33093 plugin/disks/information_schema_disks.cc doesn't compile on Solaris

second part of the fix by Rainer Orth

config.h.cmake

@@ -72,6 +72,7 @@
 #cmakedefine HAVE_SYS_IPC_H 1
 #cmakedefine HAVE_SYS_MALLOC_H 1
 #cmakedefine HAVE_SYS_MMAN_H 1
+#cmakedefine HAVE_SYS_MNTENT_H 1
 #cmakedefine HAVE_SYS_NDIR_H 1
 #cmakedefine HAVE_SYS_PTE_H 1
 #cmakedefine HAVE_SYS_PTEM_H 1

plugin/disks/CMakeLists.txt

@@ -5,6 +5,8 @@ CHECK_SYMBOL_EXISTS (getmntent "sys/mnttab.h" HAVE_GETMNTENT_IN_SYS_MNTAB)
 CHECK_SYMBOL_EXISTS (setmntent "mntent.h" HAVE_SETMNTENT)
 CHECK_SYMBOL_EXISTS (getmntinfo "sys/types.h;sys/mount.h" HAVE_GETMNTINFO)
 
+CHECK_INCLUDE_FILES (sys/mntent.h HAVE_SYS_MNTENT_H)
+
 IF (HAVE_GETMNTINFO)
 CHECK_CXX_SOURCE_COMPILES("
 #include <sys/types.h>

plugin/disks/information_schema_disks.cc

@@ -19,19 +19,18 @@
 #include <sys/types.h>
 #if defined(HAVE_GETMNTENT)
 #include <mntent.h>
-#elif defined(HAVE_SYS_MNTENT)
-#include <sys/mntent.h>
-#elif !defined(HAVE_GETMNTINFO_TAKES_statvfs)
+#elif defined(HAVE_GETMNTINFO) && !defined(HAVE_GETMNTINFO_TAKES_statvfs)
 /* getmntinfo (the not NetBSD variants) */
 #include <sys/param.h>
-#if defined(HAVE_SYS_UCRED)
 #include <sys/ucred.h>
-#endif
 #include <sys/mount.h>
 #endif
 #if defined(HAVE_GETMNTENT_IN_SYS_MNTAB)
 #include <sys/mnttab.h>
 #define HAVE_GETMNTENT
+#if defined(HAVE_SYS_MNTENT_H)
+#include <sys/mntent.h>
+#endif
 #endif
 #include <sql_class.h>
 #include <table.h>