[PAL,LibOS] Replace malloc_copy() with alloc_and_copy()

Previously, Gramine had two generic functions doing the same thing.
Remove one of them.

Signed-off-by: Dmitrii Kuvaiskii <dmitrii.kuvaiskii@intel.com>

libos/include/libos_utils.h

@@ -28,7 +28,6 @@ int init_slab(void);
 
 void* malloc(size_t size);
 void free(void* mem);
-void* malloc_copy(const void* mem, size_t size);
 
 /* ELF binary loading */
 struct link_map;

libos/src/libos_malloc.c

@@ -135,14 +135,6 @@ void* realloc(void* ptr, size_t new_size) {
 }
 #endif
 
-// Copies data from `mem` to a newly allocated buffer of a specified size.
-void* malloc_copy(const void* mem, size_t size) {
-    void* buff = malloc(size);
-    if (buff)
-        memcpy(buff, mem, size);
-    return buff;
-}
-
 void free(void* mem) {
     if (memory_migrated(mem)) {
         return;

pal/include/pal_internal.h

@@ -288,7 +288,6 @@ void pal_disable_early_memory_bookkeeping(void);
 
 void init_slab_mgr(void);
 void* malloc(size_t size);
-void* malloc_copy(const void* mem, size_t size);
 void* calloc(size_t num, size_t size);
 void free(void* mem);
 

pal/src/pal_streams.c

@@ -100,7 +100,7 @@ static int parse_stream_uri(const char** uri, char** prefix, struct handle_ops**
     *uri = p;
 
     if (prefix) {
-        *prefix = malloc_copy(u, p - u);
+        *prefix = alloc_and_copy(u, p - u);
         if (!*prefix)
             return -PAL_ERROR_NOMEM;
         /* We don't want ':' in prefix, replacing that with nullbyte which also ends the string. */

pal/src/slab.c

@@ -83,16 +83,6 @@ void* malloc(size_t size) {
     return ptr;
 }
 
-// Copies data from `mem` to a newly allocated buffer of a specified size.
-void* malloc_copy(const void* mem, size_t size) {
-    void* nmem = malloc(size);
-
-    if (nmem)
-        memcpy(nmem, mem, size);
-
-    return nmem;
-}
-
 void* calloc(size_t num, size_t size) {
     size_t total;
     if (__builtin_mul_overflow(num, size, &total))