context: Remove unnecessary checks, add comment

Author: fwsGonzo

src/kernel/context.cpp

@@ -31,7 +31,6 @@ void Context::jump(void* location, context_func func)
 {
   // store so we can call it later
   destination = func;
-  assert(destination);
   // switch to stack from @location
   __context_switch((uintptr_t) location);
 }
@@ -40,10 +39,10 @@ void Context::create(unsigned stack_size, context_func func)
 {
   // store so we can call it later
   destination = func;
-  assert(destination);
   // create and switch to new stack
   char* stack_mem = new char[stack_size];
   assert(stack_mem);
+  // aligned to 16 byte boundary
   uintptr_t start = (uintptr_t) (stack_mem+stack_size) & ~0xF;
   __context_switch(start);
   delete[] stack_mem;