[GCC4] fix warnings in sdla.h and if_frad.h

[GCC4] fix warnings in sdla.h and if_frad.h

This patch fixes these warnings with gcc 4 :

In file included from sdla.c:61:
/usr/src/git/linux-2.4/include/linux/if_frad.h:134: warning: 'packed' attribute ignored for field of type 'unsigned char'
/usr/src/git/linux-2.4/include/linux/if_frad.h:137: warning: 'packed' attribute ignored for field of type 'unsigned char'
/usr/src/git/linux-2.4/include/linux/if_frad.h:139: warning: 'packed' attribute ignored for field of type 'unsigned char'
/usr/src/git/linux-2.4/include/linux/if_frad.h:140: warning: 'packed' attribute ignored for field of type 'unsigned char[2u]'
In file included from sdla.c:63:
/usr/src/git/linux-2.4/include/linux/sdla.h:296: warning: 'packed' attribute ignored for field of type 'char'
/usr/src/git/linux-2.4/include/linux/sdla.h:297: warning: 'packed' attribute ignored for field of type 'char'
/usr/src/git/linux-2.4/include/linux/sdla.h:299: warning: 'packed' attribute ignored for field of type 'char'
/usr/src/git/linux-2.4/include/linux/sdla.h:301: warning: 'packed' attribute ignored for field of type 'char'
(...)