After commit 9b93f7e32774 ("tools/getdelays: use the static UAPI headers
from tools/include/uapi"), the Makefile was changed to use
-I../include/uapi/ instead of -I../../usr/include to ensure tools always
use the up-to-date UAPI headers.

However, only linux/taskstats.h was added to tools/include/uapi/ in commit
e5bbb35a07b3 ("tools headers UAPI: sync linux/taskstats.h"), but
linux/acct.h was missing.

This causes procacct.c to fail to compile with:

procacct.c:234:37: error: 'AGROUP' undeclared (first use in this function)

gcc -I../include/uapi/    getdelays.c   -o getdelays
gcc -I../include/uapi/    procacct.c   -o procacct
procacct.c: In function `print_procacct':
procacct.c:234:37: error: `AGROUP' undeclared (first use in this function)
did you mean `NOGROUP'?
  234 |  , t->version >= 12 ? (t->ac_flag & AGROUP ? 'P' : 'T') : '?'
      |                                     ^~~~~~
      |                                     NOGROUP
procacct.c:234:37: note: each undeclared ident

because procacct.c uses the AGROUP macro defined in linux/acct.h.

Add the missing linux/acct.h to complete the static UAPI header set.

Link: https://lore.kernel.org/20260527213558929EhiHHy9EDTMjmg3uuDOMi@zte.com.cn
Fixes: 9b93f7e32774 ("tools/getdelays: use the static UAPI headers from tools/include/uapi")
Signed-off-by: Wang Yaxin <wang.yaxin@zte.com.cn>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Cc: Fan Yu <fan.yu9@zte.com.cn>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yang Yang <yang.yang29@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>