I was getting the same problem after installing kernel-power latest version (53). I did the following to fix it.

Not sure if these steps will work for others, but documenting anyway as it worked for me.

1. Uninstalled kernel-power and reinstalled stock kernel after making a backup of the radio kernel module.

$ cp /lib/modules/current/radio-bcm2048.ko ~/radio-bcm2048.ko.new

2. Rebooted.
3. Copied the radio kernel module of stock kernel to home directory.

$ cd /lib/modules/current
$ sudo cp radio-bcm2048.ko ~
4. Installed kernel-power again.
5. Copied the stock version of radio kernel module back to /lib/modules/current .

$ cd /lib/modules/current
$ sudo cp ~/radio-bcm2048.ko .
6. Rebooted.

Upon reboot and launching FM radio, you will get the same error since the old module won't load in the new kernel. Now,

7. Copy back the actual module again.

$ sudo cp ~/radio-bcm2048.ko.new /lib/modules/current/radio-bcm2048.ko
8. Load it

$ sudo modprobe radio-bcm2048

9. A dmesg shows me the following messages.

[ 2177.886901] radio_bcm2048: disagrees about version of symbol struct_module
[ 2181.590332] radio_bcm2048: disagrees about version of symbol struct_module
[ 2230.163513] I2C driver for BCM2048 FM Radio Receiver
[ 2230.202178] bcm2048 3-0022: BCM2048 Version 0x0

The same message comes but the module is loaded now correctly.

I am listening to FM radio using kernel-power53 while writing this post.