genxml: Fix decoder to print the array element on field members.

genxml: Fix decoder to print the array element on field members.

Previously we'd print things like:

   0xfffbb568:  0x00010000 : Dword 1
       ReadLength: 0
       ReadLength: 1
   0xfffbb568:  0x00000001 : Dword 1
       ReadLength: 1
       ReadLength: 0

instead of the more obvious:

   0xfffbb568:  0x00010000 : Dword 1
       ReadLength[0]: 0
       ReadLength[1]: 1
   0xfffbb568:  0x00000001 : Dword 1
       ReadLength[2]: 1
       ReadLength[3]: 0

(Yes, the ralloc context here is bogus - the decoder leaks just about
everything.  We need to use proper ralloc contexts someday...)

Acked-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>