Merge AIX and Cygwin with the majority of platforms

Author: Endilll

llvm/cmake/config-ix.cmake

@@ -17,26 +17,7 @@ include(CheckCompilerVersion)
 include(CheckProblematicConfigurations)
 include(HandleLLVMStdlib)
 
-if (ANDROID OR CMAKE_SYSTEM_NAME MATCHES "DragonFly|FreeBSD|Haiku|Linux|NetBSD|OpenBSD|SunOS")
-  set(HAVE_DLFCN_H 1)
-  set(HAVE_ERRNO_H 1)
-  set(HAVE_FCNTL_H 1)
-  set(HAVE_FENV_H 1)
-  set(HAVE_MACH_MACH_H 0)
-  set(HAVE_MALLOC_MALLOC_H 0)
-  set(HAVE_PTHREAD_H 1)
-  set(HAVE_SIGNAL_H 1)
-  set(HAVE_SYS_IOCTL_H 1)
-  set(HAVE_SYS_MMAN_H 1)
-  set(HAVE_SYS_PARAM_H 1)
-  set(HAVE_SYS_RESOURCE_H 1)
-  set(HAVE_SYS_STAT_H 1)
-  set(HAVE_SYS_TIME_H 1)
-  set(HAVE_SYS_TYPES_H 1)
-  set(HAVE_SYSEXITS_H 1)
-  set(HAVE_TERMIOS_H 1)
-  set(HAVE_UNISTD_H 1)
-elseif (CMAKE_SYSTEM_NAME STREQUAL "AIX" OR CYGWIN)
+if (ANDROID OR CYGWIN OR CMAKE_SYSTEM_NAME MATCHES "AIX|DragonFly|FreeBSD|Haiku|Linux|NetBSD|OpenBSD|SunOS")
   set(HAVE_DLFCN_H 1)
   set(HAVE_ERRNO_H 1)
   set(HAVE_FCNTL_H 1)