scripts/wrapper: fix wrong test when checking access to the reall tool

In C, the proper syntax for a bit-wise OR is a single '|', not two.

It worked so far because all was well:
- X_OK == 1
- R_OK||X_OK == 1
- the file we searched for had the x-bit set
-> access( file, R_OK||X_OK ) worked
- inicidentally, the file we searched for also had the r-bit set,
but we were not testing that in fact.
(transplanted from eebcaff6626f09af4f69b7b06f1246a06769d0af)

 # dmalloc debug facility

 # depends on ! BACKEND

 config DEBUG_dmalloc

     bool

 choice

     bool

     prompt "dmalloc version"

 # Don't remove next line

 # CT_INSERT_VERSION_BELOW

 config DMALLOC_V_5_5_2

     bool

     prompt "5.5.2"

 endchoice

 config DMALLOC_VERSION

     string

 # Don't remove next line

 # CT_INSERT_VERSION_STRING_BELOW

     default "5.5.2" if DMALLOC_V_5_5_2