uncrypt: Suppress the compiler warnings on LP64.

We have the following warnings when compiling uncrypt on LP64 (e.g.
aosp_angler-userdebug).

bootable/recovery/uncrypt/uncrypt.cpp:77:53: warning: format specifies type 'long long' but the argument has type 'off64_t' (aka 'long') [-Wformat]
        ALOGE("error seeking to offset %lld: %s\n", offset, strerror(errno));
                                       ~~~~         ^~~~~~
                                       %ld
bootable/recovery/uncrypt/uncrypt.cpp:84:54: warning: format specifies type 'long long' but the argument has type 'unsigned long' [-Wformat]
            ALOGE("error writing offset %lld: %s\n", (offset + written), strerror(errno));
                                        ~~~~         ^~~~~~~~~~~~~~~~~~
                                        %lu
bootable/recovery/uncrypt/uncrypt.cpp:246:16: warning: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'off_t' (aka 'long') [-Wsign-compare]
    while (pos < sb.st_size) {
           ~~~ ^ ~~~~~~~~~~

According to POSIX spec [1], we have:
  off_t and blksize_t shall be signed integer types;
  size_t shall be an unsigned integer type;
  blksize_t and size_t are no greater than the width of type long.

And on Android, we always have a 64-bit st_size from stat(2)
(//bionic/libc/include/sys/stat.h).

Fix the type and add necessary casts to suppress the warnings.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_types.h.html

Change-Id: I5d64d5b7919c541441176c364752de047f9ecb20
1 file changed