hw: replace 'placement new' with 'construct_at<>'

Placement new can be misleading, as we already overload the new operator
to construct objects via pointers to allocators. To prohibit any problems here,
and to use one consistent approach, we can explicitely construct the object
with the already available 'construct_at' template function.

Ref #1443

repos/base-hw/src/core/include/page_slab.h

@@ -18,6 +18,7 @@
 #include <base/stdint.h>
 #include <util/list.h>
 #include <util/bit_allocator.h>
+#include <util/construct_at.h>
 
 #include <core_mem_alloc.h>
 
@@ -73,8 +74,6 @@ class Genode::Page_slab : public Genode::Allocator
 				indices.free(off / SLAB_SIZE);
 				return true;
 			}
-
-			void * operator new (size_t, void * p) { return p; }
 		};
 
 		Slab_block _initial_sb __attribute__((aligned(1 << ALIGN_LOG2))); /*
@@ -148,7 +147,7 @@ class Genode::Page_slab : public Genode::Allocator
 			                                   ALIGN_LOG2).is_ok()) {
 				throw Out_of_memory();
 			}
-			Slab_block *b = new (p) Slab_block();
+			Slab_block *b = Genode::construct_at<Slab_block>(p);
 			_b_list.insert(&b->list_elem);
 			_free_slab_entries += SLABS_PER_BLOCK;
 			_in_alloc = false;

repos/base-hw/src/core/include/spec/arm/short_translation_table.h

@@ -456,11 +456,6 @@ class Genode::Translation_table
 
 	public:
 
-		/**
-		 * Placement new
-		 */
-		void * operator new (size_t, void * p) { return p; }
-
 		/**
 		 * Constructor
 		 */