aarch64: vvc: Fix compilation of alf.S with MSVC 2022 17.7 and older

Use the "ldur" instruction explicitly, instead of having the
assembler implicitly convert "ldr" instructions to "ldur".

This fixes build errors like these:

libavcodec\aarch64\vvc\alf.o.asm(1023) : error A2518: operand 2: Memory offset must be aligned
        ldr             q22, [x3, #24]
libavcodec\aarch64\vvc\alf.o.asm(1024) : error A2518: operand 2: Memory offset must be aligned
        ldr             q24, [x2, #24]
libavcodec\aarch64\vvc\alf.o.asm(1393) : error A2518: operand 2: Memory offset must be aligned
        ldr             q22, [x3, #24]
libavcodec\aarch64\vvc\alf.o.asm(1394) : error A2518: operand 2: Memory offset must be aligned
        ldr             q24, [x2, #24]

Signed-off-by: Martin Storsjö <martin@martin.st>

libavcodec/aarch64/vvc/alf.S

@@ -81,8 +81,8 @@
     .endif
         ldr             q0, [clip]                  // clip
         ldr             q1, [filter]                // filter
-        ldr             q22, [clip, #24]            // clip
-        ldr             q24, [filter, #24]          // filter
+        ldur            q22, [clip, #24]            // clip
+        ldur            q24, [filter, #24]          // filter
 
         ldr             x5, [pp]                    // x5: p0
         ldr             x6, [pp, #(5*8)]            // x6: p5