flash_fp_mcu: remove config for nami-kernelnext
flash_fp_mcu: remove config for nami-kernelnext

nami-kernelnext config points to nami config.

BUG=b:236639739
BRANCH=None
TEST= run flash_fp_mcu on bard with nami-kernelnext, check that nami
config is used

Signed-off-by: Josie Nordrum <9008f8648f950c165c32e60dd421363d02445bb1@google.com>
Change-Id: Ic0fd2252dc3247d7f87246ec1ae1d84dc9738794
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3715435
Commit-Queue: Josie Nordrum <15709ebcc9b54f095b12491b186117e19e6ed974@google.com>
Reviewed-by: Craig Hesling <383db090fd8ef907a606ac8a9eccd2962bc489cf@chromium.org>
Tested-by: Josie Nordrum <15709ebcc9b54f095b12491b186117e19e6ed974@google.com>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec