Merge revisions 14230, 14602, and 14604 from the BUF_REMOVAL branch to trunk.

Merge revisions 14230, 14602, and 14604 from the BUF_REMOVAL branch to trunk.
The change eliminates the fixed size buffers in gen_suppression and
show_used_suppressions. This is achieved by changing the return type from
VG_TDICT_CALL(tool_get_extra_suppression_info and
VG_TDICT_CALL(tool_print_extra_suppression_use from Bool to SizeT.
A return value of 0 indicates that nothing (except the terminating '\0'
which is always inserted) was written to the buffer. This corresponds to the
previous False return value. A return value which is equal to the buffer
size (that was passed in as function argument) indicates that the buffer was
not large enough. The caller then resizes the buffer and retries.
Otherwise, the buffer was large enough.
Regtested with a resize value of 1.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14606