treewide: Use struct_size() for devm_kmalloc() and friends

Replaces open-coded struct size calculations with struct_size() for
devm_*, f2fs_*, and sock_* allocations. Automatically generated (and
manually adjusted) from the following Coccinelle script:

// Direct reference to struct field.
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(HANDLE, sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(HANDLE, struct_size(VAR, ELEMENT, COUNT), GFP)

// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(HANDLE, sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(HANDLE, struct_size(VAR, ELEMENT, COUNT), GFP)

// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@

- alloc(HANDLE, sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(HANDLE, CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)

Signed-off-by: Kees Cook <keescook@chromium.org>

drivers/clk/bcm/clk-bcm2835.c

@@ -2147,8 +2147,8 @@ static int bcm2835_clk_probe(struct platform_device *pdev)
 	size_t i;
 	int ret;
 
-	cprman = devm_kzalloc(dev, sizeof(*cprman) +
-			      sizeof(*cprman->onecell.hws) * asize,
+	cprman = devm_kzalloc(dev,
+			      struct_size(cprman, onecell.hws, asize),
 			      GFP_KERNEL);
 	if (!cprman)
 		return -ENOMEM;