tpm: Pull everything related to /dev/tpmX into tpm-dev.c

CLASS-dev.c is a common idiom for Linux subsystems

This pulls all the code related to the miscdev into tpm-dev.c and makes it
static. The identical file_operation structs in the drivers are purged and the
tpm common code unconditionally creates the miscdev.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Joel Schopp <jschopp@linux.vnet.ibm.com>
Reviewed-by: Ashley Lai <adlai@linux.vnet.ibm.com>
[phuewe:
tpm_dev_release is now used only in this file, thus the EXPORT_SYMBOL
can be dropped and the function be marked as static.
It has no other in-kernel users]
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>