clk: renesas: rcar-gen2: Rename vsp1-(sy|rt) clocks to vsp(s|r)

VSP1 instances VSPS (which stands for "VSP Standard") and VSPR (which
stands for "VSP for Resizing") were wrongly named as "vsp1-sy" and
"vsp1-rt". The clock section in the SoC datasheets misunderstood the
abbreviations as meaning VSP System and VSP Realtime, and named the
corresponding clocks VSP1(SY) and VSP1(RT). This mistake has been
carried over to the kernel code.

This patch fixes this by renaming the clock names to "vsps" and "vspr".

Inspired from commit 79ea9934b8df ("ARM: shmobile: r8a7790: Rename
VSP1_(SY|RT) clocks to VSP1_(S|R)")

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20200831183722.8165-1-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: Convert to SPDX identifiers

This patch updates license to use SPDX-License-Identifier
instead of verbose license text.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
[rebased against clk-spdx]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: renesas: r8a7794: Fix LB clock divider

The CLK_TYPE_GEN2_LB clock type is meant for SoCs like R-Car H2, where
the LB clock divider depends on the value of the MD18 pin.

On R-Car E2, the LB clock divider is fixed to 24. Hence model the clock
as a fixed factor clock instead.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>

clk: renesas: r8a7794: Add rwdt clock

Add "rwdt" clock to r8a7794_mod_clks. Also, since we may need to access
the watchdog registers at any time, declare the clock as critical.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: r8a7794: Add new CPG/MSSR driver

Add a new R-Car E2 Clock Pulse Generator / Module Standby and Software
Reset driver, using the CPG/MSSR driver core. This will enable support
for module resets, which are not supported by the existing driver.

The old driver can still be used through a Kconfig option, to preserve
backward compatibility with old DTBs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>