arm64: dts: qcom: sm8550: Enable UHS-I SDR50 and SDR104 SD card modes

The restriction on UHS-I speed modes was added to all SM8550 platforms
by copying it from SM8450 dtsi file, and due to the overclocking of SD
cards it was an actually reproducible problem. Since the latter issue
has been fixed, UHS-I speed modes are working fine on SM8550 boards,
below is the test performed on SM8550-HDK:

SDR50 speed mode:

    mmc0: new UHS-I speed SDR50 SDHC card at address 0001
    mmcblk0: mmc0:0001 00000 14.6 GiB
     mmcblk0: p1

    % dd if=/dev/mmcblk0p1 of=/dev/null bs=1M count=1024
    1024+0 records in
    1024+0 records out
    1073741824 bytes (1.1 GB, 1.0 GiB) copied, 23.5468 s, 45.6 MB/s

SDR104 speed mode:

    mmc0: new UHS-I speed SDR104 SDHC card at address 59b4
    mmcblk0: mmc0:59b4 USDU1 28.3 GiB
     mmcblk0: p1

    % dd if=/dev/mmcblk0p1 of=/dev/null bs=1M count=1024
    1024+0 records in
    1024+0 records out
    1073741824 bytes (1.1 GB, 1.0 GiB) copied, 11.9819 s, 89.6 MB/s

Unset the UHS-I speed mode restrictions from the SM8550 platform dtsi
file, there is no indication that the SDHC controller is broken.

Fixes: ffc50b2 ("arm64: dts: qcom: Add base SM8550 dtsi")
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Link: https://lore.kernel.org/r/20260314023715.357512-6-vladimir.zapolskiy@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

Author: Vladimir Zapolskiy

arch/arm64/boot/dts/qcom/sm8550.dtsi

@@ -3251,9 +3251,6 @@
 			max-sd-hs-hz = <37500000>;
 			dma-coherent;
 
-			/* Forbid SDR104/SDR50 - broken hw! */
-			sdhci-caps-mask = <0x3 0>;
-
 			status = "disabled";
 
 			sdhc2_opp_table: opp-table {