hw/block/nand: Have blk_load() take unsigned offset and return boolean

Negative offset is meaningless, use unsigned type.
Return a boolean value indicating success.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20240409135944.24997-3-philmd@linaro.org>

hw/block/nand.c

@@ -84,7 +84,11 @@ struct NANDFlashState {
 
     void (*blk_write)(NANDFlashState *s);
     void (*blk_erase)(NANDFlashState *s);
-    void (*blk_load)(NANDFlashState *s, uint64_t addr, int offset);
+    /*
+     * Returns %true when block containing (@addr + @offset) is
+     * successfully loaded, otherwise %false.
+     */
+    bool (*blk_load)(NANDFlashState *s, uint64_t addr, unsigned offset);
 
     uint32_t ioaddr_vmstate;
 };
@@ -772,11 +776,11 @@ static void glue(nand_blk_erase_, NAND_PAGE_SIZE)(NANDFlashState *s)
     }
 }
 
-static void glue(nand_blk_load_, NAND_PAGE_SIZE)(NANDFlashState *s,
-                uint64_t addr, int offset)
+static bool glue(nand_blk_load_, NAND_PAGE_SIZE)(NANDFlashState *s,
+                                                 uint64_t addr, unsigned offset)
 {
     if (PAGE(addr) >= s->pages) {
-        return;
+        return false;
     }
 
     if (s->blk) {
@@ -804,6 +808,8 @@ static void glue(nand_blk_load_, NAND_PAGE_SIZE)(NANDFlashState *s,
                         offset, NAND_PAGE_SIZE + OOB_SIZE - offset);
         s->ioaddr = s->io;
     }
+
+    return true;
 }
 
 static void glue(nand_init_, NAND_PAGE_SIZE)(NANDFlashState *s)