lib: c: combine libc and ulibc

libc is now made up of several independent components, each of which is individually compiled into a static library.
they are then all combined into a single shared library.

lib/libc/malloc/stdlib/malloc.c

@@ -0,0 +1,44 @@
+#include <heap/heap.h>
+
+#ifdef ENABLE_GLOBAL_HEAP
+static heap_t global_heap = HEAP_INIT;
+
+void *malloc(size_t count)
+{
+	return heap_alloc(&global_heap, count);
+}
+
+void *calloc(size_t count, size_t size)
+{
+	return heap_calloc(&global_heap, count, size);
+}
+
+void *realloc(void *p, size_t count)
+{
+	return heap_realloc(&global_heap, p, count);
+}
+
+void free(void *p)
+{
+	heap_free(&global_heap, p);
+}
+#else
+void *malloc(size_t count)
+{
+	return NULL;
+}
+
+void *calloc(size_t count, size_t size)
+{
+	return NULL;
+}
+
+void *realloc(void *p, size_t count)
+{
+	return NULL;
+}
+
+void free(void *p)
+{
+}
+#endif