AK+LibX86: Generalize u128/256 to AK::UFixedBigInt

Doing these as custom classes might be faster, especially when writing
them in SSE, but this would cause a lot of Code duplication and due to
the nature of constexprs and the intelligence of the compiler they might
be using SSE/MMX either way

Userland/Libraries/LibX86/CMakeLists.txt

@@ -1,6 +1,5 @@
 set(SOURCES
     Instruction.cpp
-    Types/Formatter.cpp   
 )
 
 serenity_lib(LibX86 x86)