staging: sm750fb: removed line continuations in quoted strings

checkpatch gives WARNING: Avoid line continuations in quoted strings.

Trivial fix by removing line continuations and adding another quote at
the start of next line.

Signed-off-by: Prasant Jalan <prasant.jalan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>