Fix bpf_trace_printk() for big-endian targets
Fix bpf_trace_printk() for big-endian targets

The format string for bpf_trace_printk() gets garbled during the
conversion of the LLVM IR code to the corresponding BPF object.
This happens because bcc explicitly sets the data layout of the
module to 'e-m:e-p:64:64-i64:64-n32:64-S128' which is valid for
little-endian targets only. If the arch is set to 'bpf', LLVM
selects the correct data layout automatically and there is no
need to set this explicitly.

Signed-off-by: Sandipan Das <ae8113f64d9c72812e097938d25a8975da69c074@linux.vnet.ibm.com>
Reported-by: Chandan Rajendra <5b09eece4a5b11d5d0125c0f7eca424d593874ed@linux.vnet.ibm.com>
Fixes: #1723

mcaleavya/bcc,iovisor/bcc,iovisor/bcc,mcaleavya/bcc,iovisor/bcc,tuxology/bcc,tuxology/bcc,iovisor/bcc,brendangregg/bcc,mcaleavya/bcc,brendangregg/bcc,iovisor/bcc,mcaleavya/bcc,tuxology/bcc,brendangregg/bcc,tuxology/bcc,mcaleavya/bcc,brendangregg/bcc,brendangregg/bcc,tuxology/bcc