tpm_regs: clean up debug messages
tpm_regs: clean up debug messages

Some debug messages were a bit ambiguous, and some just wrong, this
patch fixes the wrong one and disambiguates the other two.

BRANCH=none
BUG=none
TEST=observed the new generated message.

Change-Id: I2b58ec050816ecdfe4b20dd8410910569767830d
Signed-off-by: Vadim Bendebury <5515d6d2d0829cbe0dd0dcf2094aaded06d58514@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/340536
Reviewed-by: Bill Richardson <129945214b1d548d8e49b6c29c43094f8c78057f@chromium.org>

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