rng: eliminate common.h include from RNG drivers

Usage of common.h is deprecated.

* Remove common.h from RNG drivers.
* Sort includes.
* Add time.h to sandbox driver.
* Add linux/types.h to rng.h to provide size_t.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

doc: random number generation

Add random number generation APIs to the HTML documentation.
Fix style issues.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

dm: rng: Add random number generator(rng) uclass

Add a uclass for reading a random number seed from a random number
generator device.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

doc: random number generation

Add random number generation APIs to the HTML documentation.
Fix style issues.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

dm: rng: Add random number generator(rng) uclass

Add a uclass for reading a random number seed from a random number
generator device.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

dm: rng: Add random number generator(rng) uclass

Add a uclass for reading a random number seed from a random number
generator device.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>