Documentation/i2c: fix spelling error in i2c-address-translators

Correct to "stretched" from "streched" in "keeps clock streched on bus A
waiting for reply".

Signed-off-by: Attreyee Mukherjee <tintinm2017@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>