RFREQ is a 38-bit number, with the 10 MSB
the integer part and the 28 LSB the fractional
part. So, we need to divide RFEQ by 2^28 prior
to the calculation.

This was causing a segfault when reading the frequency

As libbpmclient changed, we need to update it there too.

In this way, we can standardize how the
functions are called and handled.

This fixes #115 github issue

Note that this requires at least
lnls-dig/bpm-gw@27a4af84b1

This is necessary as lnls-dig/bpm-gw@6a78088ab1
and lnls-dig/bpm-gw@950b4b2d18

This causes an assertion error as the zactor
infrastructure needs the PIPE after the thread exits.

This fixes #116 github issue.

In this way we can guarantee that these functions
will be thread-safe even if other SMIOs calls them.

The previous implementation was not thread-safe.

We should replace this functions by sending a
message to the DEVIO instance through the
PIPE management.

This will allow DEVIO clients to register SMIOs
by sending messages to its pipe.

This pipe will be used to allow other SMIOs to
register new SMIOs

It's better to first attach the SMIO to its
parent (its DEVIO handler) and then initialize
the SMIO.

The SMIO might need something from the
DEVIO.

This, together with commits from c171576c
to bbe05bf6 fixes #115 github issue

In this way, we reduce code repetition and
maintenance becomes easier