[TLI] Add SLEEFGNUABI mappings for fmod/fmodf fixed-width. (llvm#75803)

Cleanup test sleef-calls-aarch64.ll:
- make the util update script's regex more clear
- eliminate scalar epilogues in tests

Author: paschalis-mpeis

llvm/include/llvm/Analysis/VecFuncs.def

@@ -493,6 +493,7 @@ TLI_DEFINE_VECFUNC( "llvm.exp2.f64", "_ZGVnN2v_exp2", FIXED(2), "_ZGV_LLVM_N2v")
 
 TLI_DEFINE_VECFUNC( "exp10", "_ZGVnN2v_exp10", FIXED(2), "_ZGV_LLVM_N2v")
 TLI_DEFINE_VECFUNC( "llvm.exp10.f64", "_ZGVnN2v_exp10", FIXED(2), "_ZGV_LLVM_N2v")
+TLI_DEFINE_VECFUNC("fmod", "_ZGVnN2vv_fmod", FIXED(2), "_ZGV_LLVM_N2vv")
 
 TLI_DEFINE_VECFUNC( "lgamma", "_ZGVnN2v_lgamma", FIXED(2), "_ZGV_LLVM_N2v")
 
@@ -546,6 +547,7 @@ TLI_DEFINE_VECFUNC( "llvm.exp2.f32", "_ZGVnN4v_exp2f", FIXED(4), "_ZGV_LLVM_N4v"
 
 TLI_DEFINE_VECFUNC( "exp10f", "_ZGVnN4v_exp10f", FIXED(4), "_ZGV_LLVM_N4v")
 TLI_DEFINE_VECFUNC( "llvm.exp10.f32", "_ZGVnN4v_exp10f", FIXED(4), "_ZGV_LLVM_N4v")
+TLI_DEFINE_VECFUNC("fmodf", "_ZGVnN4vv_fmodf", FIXED(4), "_ZGV_LLVM_N4vv")
 
 TLI_DEFINE_VECFUNC( "lgammaf", "_ZGVnN4v_lgammaf", FIXED(4), "_ZGV_LLVM_N4v")