pstore/zone: fix a kernel-doc markup

The documented struct is psz_head and not psz_buffer.

Reviewed-by: Kees Cook <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>
Link: https://lore.kernel.org/r/a67ca4[e-mail]
Signed-off-by: Jonathan Corbet <[e-mail]>

fs/pstore/zone.c

···
 #include "internal.h"
 
 /**
- * struct psz_head - header of zone to flush to storage
+ * struct psz_buffer - header of zone to flush to storage
  *
  * @sig: signature to indicate header (PSZ_SIG xor PSZONE-type value)
  * @datalen: length of data in @data