fs: rework f2fs

Signed-off-by: arter97 <qkrwngud825@gmail.com>
Makefiles: compiler option overhaul #2

 - Remove all cutting-edge flags

   Linux kernel should be stable what-so-ever.
   I've found numerous articles on the web that
   GCC optimization flags can actually hurt "very much".

   Let's go back to the conservative step; disable the followings :
   -Ofast -fno-tree-vectorize -fmodulo-sched -fmodulo-sched-allow-regmoves -fno-inline-functions -funroll-loops

 - Go back to soft-float

   @GeeckoDev have tipped me, that the Linux kernel actually does not use
   the floating-point calculation.
   Using hard-float is non-standard and can hurt.
   So go back to soft-float.

 - Use vfpv4 instead of neon for mfpu flag

   GCC neon code generation can end up in funky behaviours.
   There are beneficial codes that explicitly defines '-mfpu=neon',
   so disable neon globally.

 - Disable PIC code generation

   Seems like Linux kernel is not being friendly with PIC code generation.
   Reference : https://android.googlesource.com/kernel/common.git/+/b2a582d102c4deb9e6a34f784e0700f642c50e8a

Signed-off-by: arter97 <qkrwngud825@gmail.com>