[libc][math][c23] removed dsubl for 32 arm (llvm#101423)

Author: aaryanshukla

libc/config/linux/arm/entrypoints.txt

@@ -230,7 +230,6 @@ set(TARGET_LIBM_ENTRYPOINTS
     libc.src.math.coshf
     libc.src.math.dfmal
     libc.src.math.dsqrtl
-    libc.src.math.dsubl
     libc.src.math.erff
     libc.src.math.exp
     libc.src.math.exp10