mkvparser: set kMaxAllocSize explicitly
mkvparser: set kMaxAllocSize explicitly

removes the need for the unrelated INT32_MAX and fixes the build
(stdint.h was missing)

Change-Id: Idf3315097982aec6fb28030bd2327ba6cff14668

zofuthan/libwebm,felipebetancur/libwebm,zofuthan/libwebm,webmproject/libwebm,webmproject/libwebm,webmproject/libwebm,felipebetancur/libwebm