lzop: unbreak powerpc build with GCC >= 5

lzop: unbreak powerpc build with GCC >= 5

Fixes:
http://autobuild.buildroot.net/results/c60/c60554f7b84d5050b86c1735fb857856ddfa4dff/
http://autobuild.buildroot.net/results/888/888ea1aea200a71d0887754e2afabdc6b260bf2f/
http://autobuild.buildroot.net/results/219/219194d269d7f3cf4c3db120e6d8079085916bd3/

GCC >= 5 changed the behaviour of 'extern inline', causing linking errors
when the powerpc inline functions are used in multiple compilation units:

https://gcc.gnu.org/gcc-5/porting_to.html

Add a patch from openembedded to change it to use static inline (which has
the correct behaviour in both old/new GCC versions) to fix it.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>