TS 7200 kernel image size

[Thomas Klausner <wiz%NetBSD.org@localhost>]

The file gzimg_TS7200_wd0_flash_0x60660000 grew as follows over the
releases (gunzipped):

3.1.1: 1386260 bytes/0x152714
4.0.1: 1496617 bytes/0x16D629
5.0:   1666084 bytes/0x196C24

If I understand the "fis list" output of my TS7200 correctly:
RedBoot> fis list
Name              FLASH addr  Mem addr    Length      Entry point
(reserved)        0x60000000  0x60000000  0x00620000  0x00000000
RedBoot           0x60620000  0x60620000  0x00040000  0x00000000
RedBoot config    0x607C0000  0x607C0000  0x00001000  0x00000000
FIS directory     0x607E0000  0x607E0000  0x00020000  0x00000000

only the space from 0x60660000 to 0x607C0000 is available for the
NetBSD kernel image which is 0x160000 bytes; that means only the 3.1.1
kernel is small enough to fit.

What do you suggest to fit a newer NetBSD kernel?
 Thomas