CMake: Add initial support for MidnightBSD (#1377)

* Add initial support for MidnightBSD

* Cleanup some issues identified through code review.

Add libzfs check as MidnightBSD does have zfs.

* Add MidnightBSD check to the version.c detection

* Remove `OR MidnightBSD` tests

* Clean up

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Co-authored-by: Carter Li <CarterLi@users.noreply.github.com>

Author: laffer1

CMakeLists.txt

@@ -20,6 +20,9 @@ elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "FreeBSD")
     set(FreeBSD TRUE CACHE BOOL "..." FORCE)
 elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "OpenBSD")
     set(OpenBSD TRUE CACHE BOOL "..." FORCE)
+elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "MidnightBSD")
+    set(FreeBSD TRUE CACHE BOOL "..." FORCE)
+    set(MidnightBSD TRUE CACHE BOOL "..." FORCE)
 elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "NetBSD")
     set(NetBSD TRUE CACHE BOOL "..." FORCE)
 elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "DragonFly")

src/detection/version/version.c

@@ -28,6 +28,8 @@
     #define FF_SYSNAME "Linux"
 #elif defined(__DragonFly__) // We define `__FreeBSD__` on DragonFly BSD for simplification
     #define FF_SYSNAME "DragonFly"
+#elif defined(__MidnightBSD__)
+    #define FF_SYSNAME "MidnightBSD"
 #elif defined(__FreeBSD__)
     #define FF_SYSNAME "FreeBSD"
 #elif defined(__APPLE__)