thermal: exynos: Add TMU support for Exynos7 SoC

Add registers, bit fields and compatible strings for Exynos7 TMU
(Thermal Management Unit). Following are a few of the differences
in the Exynos7 TMU from earlier SoCs:
        - 8 trigger levels
        - Different bit offsets and more registers for the rising
        and falling thresholds.
        - New power down detection bit in the TMU_CONTROL register
        which does not update the CURRENT_TEMP0 when tmu power down
        is detected.
        - Change in bit offset for the NEXT_DATA field of EMUL_CON
        register. EMUL_CON register address has also changed.
        - INTSTAT and INTCLEAR registers present in earlier SoCs
        have been combined into one INTPEND register. The register
        address for INTCLEAR and INTPEND is also different.
        - Since there are 8 rising/falling interrupts as against
        at most 4 in earlier SoCs the INTEN bit offsets are different.
        - Multiple probe support which is handled by a TMU_CONTROL1
        register (No support for this in the current patch).

This patch adds special clock support required only for Exynos7. It
also updates the "code_to_temp" prototype as Exynos7 has 9 bit
code-temp mapping.

Acked-by: Lukasz Majewski <l.majewski@samsung.com>
Tested-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>