aarch/fpu: use generic builtins based math functions
introduce sysdep header math-use-builtins.h to replace aarch64
implementations with corresponding generic ones.
- newly inroduced generic sqrt{,f}, fma{,f}
- existing floor{,f}, nearbyint{,f}, rint{,f}, round{,f}, trunc{,f}
- Note that generic copysign was already enabled (via generic
math-use-builtins.h) now thru sysdep header
Tested with build-many-glibcs for aarch64-linux-gnu
This is a non functional change and aarch64 libm before/after was
byte invariant as compared below:
| cd /SCRATCH/vgupta/gnu/install-glibc-A-baseline
| for i in `find . -name libm-2.31.9000.so`; do
| echo $i; diff $i /SCRATCH/vgupta/gnu/install-glibc-C-reduce-scope/$i ;
| echo $?;
| done