dt-bindings: PCI: qcom,pcie-sc8180x: Drop unrelated clocks from PCIe hosts

The TBU clock belongs to the Translation Buffer Unit, part of the SMMU.
The ref clock is already being driven upstream through some of the
branches.

Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20250521-topic-8150_pcie_drop_clocks-v1-1-3d42e84f6453@oss.qualcomm.com

Documentation/devicetree/bindings/pci/qcom,pcie-sc8180x.yaml

@@ -33,8 +33,8 @@ properties:
       - const: mhi # MHI registers
 
   clocks:
-    minItems: 8
-    maxItems: 8
+    minItems: 6
+    maxItems: 6
 
   clock-names:
     items:
@@ -44,8 +44,6 @@ properties:
       - const: bus_master # Master AXI clock
       - const: bus_slave # Slave AXI clock
       - const: slave_q2a # Slave Q2A clock
-      - const: ref # REFERENCE clock
-      - const: tbu # PCIe TBU clock
 
   interrupts:
     minItems: 8
@@ -117,17 +115,13 @@ examples:
                      <&gcc GCC_PCIE_0_CFG_AHB_CLK>,
                      <&gcc GCC_PCIE_0_MSTR_AXI_CLK>,
                      <&gcc GCC_PCIE_0_SLV_AXI_CLK>,
-                     <&gcc GCC_PCIE_0_SLV_Q2A_AXI_CLK>,
-                     <&gcc GCC_PCIE_0_CLKREF_CLK>,
-                     <&gcc GCC_AGGRE_NOC_PCIE_TBU_CLK>;
+                     <&gcc GCC_PCIE_0_SLV_Q2A_AXI_CLK>;
             clock-names = "pipe",
                           "aux",
                           "cfg",
                           "bus_master",
                           "bus_slave",
-                          "slave_q2a",
-                          "ref",
-                          "tbu";
+                          "slave_q2a";
 
             dma-coherent;