Sync to upstream dtc commit b06e55c88b9b ("Prevent crash on modulo by
zero"). This adds the following commits from upstream:

b06e55c Prevent crash on modulo by zero
b433450 Fix some bugs in processing of line directives
d728ad5 Fix crash on nul character in string escape sequence
1ab2205 Gracefully handle bad octal literals
1937095 Prevent crash on division by zero
d0b3ab0 libfdt: Fix undefined behaviour in fdt_offset_ptr()
d4c7c25 libfdt: check for potential overrun in _fdt_splice()
f58799b libfdt: Add some missing symbols to version.lds
af9f26d Remove duplicated -Werror in dtc Makefile
604e61e fdt: Add functions to retrieve strings
8702bd1 fdt: Add a function to get the index of a string
2218387 fdt: Add a function to count strings
554fde2 libfdt: fix comment block of fdt_get_property_namelen()
e5e6df7 fdtdump: Fix bug printing bytestrings with negative values
067829e Remove redundant fdtdump test code
897a429 Move fdt_path_offset alias tests to right tests section
2d1417c Add simple .travis.yml
f6dbc6c guess output file format
5e78dff guess input file format based on file content or file name
8b927bf tests: convert `echo -n` to `printf`
64c46b0 Fix crash with poorly defined #size-cells

Cc: Grant Likely <grant.likely@linaro.org>
Tested-by: Frank Rowand <frank.rowand@sonymobile.com>
Reviewed-by: Frank Rowand <frank.rowand@sonymobile.com>
Signed-off-by: Rob Herring <robh@kernel.org>