[klibc] losetup: Fix warnings about __u64 arguments to printf

On some 64-bit architectures __u64 is defined as unsigned long.  On
these architectures, gcc emits a series of warnings such as:

    usr/utils/losetup.c: In function 'show_loop':
    usr/utils/losetup.c:54:21: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type '__u64' {aka 'long unsigned int'} [-Wformat=]

Define the necessary macro to ensure __u64 is defined as unsigned long
long everywhere, fixing these warnings.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
1 file changed