Reduce code stink (#1818)

CRC32.cpp:
Make table initialization compile time

DSi_NAND.cpp:
Fix file close / unmount / disk close on error
~L427: Remove redundant calls, as they are immediately rendered useless by `rem` being overwritten

NDS.cpp / FreeBIOS.h:
Remove unneeded size values in header
Remove unneeded memset's as they are initialized anyway

sha1.c / sha1.h:
Fix useless warning

Wifi.cpp:
Remove unneeded includes

DSi.cpp:
Reduce ugly casts
Deduplicate code

qt_sdl/main.cpp:
silence clang switch statement warning

qt_sdl/main.h:
fix override warnings

dolphin/BitSet.h:
use msvc extensions only when appropriate, fix broken bit set count under _WIN32

src/ROMList.cpp

@@ -6800,4 +6800,4 @@ const ROMListEntry ROMList[] =
 	{0x5A5A5242, 0x04000000, 0x00000003},
 };
 
-const size_t ROMListSize = sizeof(ROMList) / sizeof(ROMListEntry);
+const size_t ROMListEntryCount = sizeof(ROMList) / sizeof(ROMListEntry);