net: sunhme: Fix sbus regression

Commit cc216e4b44ce ("net: sunhme: Switch SBUS to devres") changed
explicit sized of_ioremap with BMAC_REG_SIZEs to
devm_platform_ioremap_resource mapping all the resource. However,
this does not work on my Sun Ultra 2 with SBUS HMEs:

hme f0072f38: error -EBUSY: can't request region for resource [mem 0x1ffe8c07000-0x1ffe8c0701f]
hme f0072f38: Cannot map TCVR registers.
hme f0072f38: probe with driver hme failed with error -16
hme f007ab44: error -EBUSY: can't request region for resource [mem 0x1ff28c07000-0x1ff28c0701f]
hme f007ab44: Cannot map TCVR registers.
hme f007ab44: probe with driver hme failed with error -16

Turns out the open-firmware resources overlap, at least on this
machines and PROM version:

hexdump /proc/device-tree/sbus@1f,0/SUNW,hme@2,8c00000/reg:
00 00 00 02 08 c0 00 00 00 00 01 08
00 00 00 02 08 c0 20 00 00 00 20 00
00 00 00 02 08 c0 40 00 00 00 20 00
00 00 00 02 08 c0 60 00 00 00 20 00
00 00 00 02 08 c0 70 00 00 00 00 20

And the driver previously explicitly mapped way smaller mmio regions:

/proc/iomem:
1ff28c00000-1ff28c00107 : HME Global Regs
1ff28c02000-1ff28c02033 : HME TX Regs
1ff28c04000-1ff28c0401f : HME RX Regs
1ff28c06000-1ff28c0635f : HME BIGMAC Regs
1ff28c07000-1ff28c0701f : HME Tranceiver Regs

Quirk this specific issue by truncating the previous resource to not
overlap into the TCVR registers.

Fixes: cc216e4b44ce ("net: sunhme: Switch SBUS to devres")
Signed-off-by: René Rebe <rene@exactco.de>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Link: https://patch.msgid.link/20260205.170959.89574674688839340.rene@exactco.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>