drm/i915/icl: Add remaining registers and bitfields for MG PHY DDI

This patch adds the remaining register definitions and bit fields
required for MG PHy DDI buffer initializations and voltage
swing programming for MG PHy DDI ports.

While at it this patch also fixes the naming for previously defined
MG PHY registers in original commit id (c92f47b5 "drm/i915/icl:
Add register defs for voltage swing sequences for MG PHY DDI").
Since the MG PHY registers are first defined in ICL platform, there
is no need for _ICL prefix.

v4 (from Paulo): add two white spaces to CRI_CALCINIT too.

v3:
* Fix register names, add spaces for MASK defines, correct the order
of #defines (Paulo)

v2:
* Change the MG_TX_DRVCTL registers names to match the spec (Anusha)

Cc: James Ausmus <james.ausmus@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1531510993-6606-1-git-send-email-manasi.d.navare@intel.com