The linux arm64 header linux:arch/arm64/include/asm/sysreg.h
contains asm statement outside the function,

========
asm(
"       .irp    num,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30\n"
"       .equ    .L__reg_num_x\\num, \\num\n"
"       .endr\n"
"       .equ    .L__reg_num_xzr, 31\n"
"\n"
"       .macro  mrs_s, rt, sreg\n"
        __emit_inst(0xd5200000|(\\sreg)|(.L__reg_num_\\rt))
"       .endm\n"
"\n"
"       .macro  msr_s, sreg, rt\n"
        __emit_inst(0xd5000000|(\\sreg)|(.L__reg_num_\\rt))
"       .endm\n"
);
========

The compiler cannot remove them since they are file scope.
This patch adds bpf asm parser to handle this, otherwise,
llvm will complain with compilation failure. Since none of
macros/defines are used in bpf program, there is no impact
in compilation result.

Another change is to add AARCH64 value to ld_cache processing.
The value is taken from glibc:sysdeps/generic/ldconfig.h.
Signed-off-by: Yonghong Song <yhs@fb.com>