docs: packing: Fix a typo in example code.

Fix misspelling of "typedef".

Signed-off-by: Collin Funk <[e-mail]>
Signed-off-by: Jonathan Corbet <[e-mail]>
Link: https://lore.kernel.org/r/e532[e-mail]

Documentation/core-api/packing.rst

···
 
    #define SIZE 13
 
-   typdef struct __packed { u8 buf[SIZE]; } packed_buf_t;
+   typedef struct __packed { u8 buf[SIZE]; } packed_buf_t;
 
    static const struct packed_field_u8 fields[] = {
            PACKED_FIELD(100, 90, struct data, field1),