CheerpBackend: Optimize generation of tmpphi variables
Introduce a new pass to lower memory intrinsics to plain loops

For all types but immutables and byte layout structures, since we
have faster code paths for memcpying them
CheerpBackend: Remove support for most memory intrinsics

We only support the ones we can accelerate in the backend, all the rest
is lowered to load/store loops
CheerpBackend: Remove some white spaces
CheerpBackend: Byte layouts structures can be memcopied without being REGULAR
Disable a pointer comparison optimization on NBA
CheerpBackend: Fix some minor PointerAnalyzer issues
CheerpBackend: Small fixes to IndirectCallOptimizer
CheerpBackend: Do not propagate the GEPs through not inlineable instructions
CheerpBackend: Remove an unused variable
CheerpBackend: Reduce the use of tmpphis even more
CheerpBackend: Support FCMP_UNO predicate
CheerpBackend: Put all allocas from NativeRewriter at the beginning of the entry block
CheerpBackend: Merge allocas of arrays of the same type into a single alloca