clk: samsung: exynos850: Implement CMU_IS domain

CMU_IS clock domain provides clocks for IS IP-core (Image Signal
Processing Subsystem). According to Exynos850 TRM, CMU_IS generates
CSIS, IPP, ITP, VRA and GDC clocks for BLK_IS.

This patch adds next clocks:
  - bus clocks in CMU_TOP needed for CMU_IS
  - all internal CMU_IS clocks
  - leaf clocks for IS IP-core, CSIS (Camera Serial Interface Slave),
    D_TZPC (TrustZone Protection Controller), CSIS DMA, GDC (Geometric
    Distortion Correction), IPP (Image Preprocessing Processing core),
    ITP (Image Texture Processing core), MCSC (Multi-Channel Scaler),
    VRA (Visual Recognition Accelerator), PPMU (Platform Performance
    Monitoring Unit), SysMMU and SysReg

IS related gate clocks in CMU_TOP were marked as CLK_IS_CRITICAL,
because:
  1. All of those have to be enabled in order to read
     /sys/kernel/debug/clk/clk_summary file
  2. When some user driver (e.g. exynos-sysmmu) disables some derived
     leaf clock, it can lead to CMU_TOP clocks disable, which then makes
     the system hang. To prevent that, the CLK_IS_CRITICAL flag is used,
     as CLK_IGNORE_UNUSED is not enough.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220809113323.29965-7-semen.protsenko@linaro.org

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