spl: dm: Kconfig: split REGMAP/SYSCON support for TPL from SPL

This change introduces TPL variants of the REGMAP and SYSCON config
options (i.e. TPL_REGMAP and TPL_SYSCON in analogy to SPL_REGMAP and
SPL_SYSCON) in preparation of a finer-grained feature selection for
building feature-rich TPL variants.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>