arm64: dts: ti: k3-am62l3-evm: Disable MMC1 internal pulls on data pins

arm64: dts: ti: k3-am62l3-evm: Disable MMC1 internal pulls on data pins

AM62L EVM has external 47K pullups on MMC1 DAT1-DAT3 pins [0].
Disable internal pullups on DAT1-DAT3 so that each line has a
single pullup source:
- with both pullups enabled, the effective parallel resistance on
  DAT1-3 (~24.2K) creates a ~2x mismatch vs DAT0 (47K external
  only). Removing internal pullups results in DAT1-3 matching DAT0 at 47K
- 47K external alone is within the recommended range for 1.8V
  signaling (10K min, 50K recommended max)
- both internal and external pullups enabled equals unnecessary power
  consumption

[0] https://www.ti.com/lit/zip/SPRCAL6

Fixes: 00fb4c73b67d ("arm64: dts: ti: k3-am62l: add initial reference board file")
Signed-off-by: Judith Mendez <jm@ti.com>
Reviewed-by: Moteen Shah <m-shah@ti.com>
Link: https://patch.msgid.link/20260223233731.2690472-3-jm@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>