Disable pr107262.c for RISC-V

RISC-V does not support the __bf16 datatype, therefore disable test.
llvm · mablinov · Sep 14, 2023 · Nov 14, 2023 · Nov 14, 2023 · Nov 22, 2023
commit 6b0a9dd13ce81cd5c02a15c4d122aa587ae966ff
diff --git a/SingleSource/Regression/C/gcc-dg/CMakeLists.txt b/SingleSource/Regression/C/gcc-dg/CMakeLists.txt
@@ -2560,6 +2560,9 @@ if(ARCH MATCHES "riscv")
     c99-tgmath-2.c
     c99-tgmath-3.c
     c99-tgmath-4.c
+
+    # RISCV does not support `__bf16`
+    pr107262.c
   )
 
   if (LIBC MATCHES "musl")