Fix temporary file name strlcpy size.
The strlcpy size argument overflows on integer sanitized builds.
runtime error: unsigned integer overflow: 11 - 35 cannot be represented
in type 'unsigned long'
This doesn't cause a problem because strlcpy stops on the null in
TMP_FILE_PATTERN, and localTmpFileName is defined large enough to
contain TMP_FILE_PATTERN.
This changes the size argument to the remaining length in the buffer,
and removes an extraneous '/' write as TMP_FILE_PATTERN already begins
with '/'.
Bug:
30969751
Test: Reran CTS test which triggered the overflow.
Change-Id: I20b5deeaaa1a863324dfd1d94f3135920eae48d3
Merged-In: I20b5deeaaa1a863324dfd1d94f3135920eae48d2
(cherry picked from commit
62fc14894b32f35641ae2b61ef7ed054c9660288)