gpgsm: Fix alignment

[NIIBE Yutaka]

Hello, Justus,

On armhf architecture, I got this warning with gcc-6:

==================
../../../gnupg/tests/gpgscm/scheme.c: In function ‘alloc_cellseg’:
../../../gnupg/tests/gpgscm/scheme.c:627:15: warning: cast increases
required alignment of target type [-Wcast-align]
          newp=(pointer)cp;
               ^
==================

I think that with modern C, we use (void *) for address.  (char *) is
specifically for character where its alignment is 1.

How about this fix?

diff --git a/tests/gpgscm/scheme-private.h b/tests/gpgscm/scheme-private.h
index 9eafe76..727e0c0 100644
--- a/tests/gpgscm/scheme-private.h
+++ b/tests/gpgscm/scheme-private.h
@@ -78,7 +78,7 @@ int tracing;
 #ifndef CELL_NSEGMENT
 #define CELL_NSEGMENT   10    /* # of segments for cells */
 #endif
-char *alloc_seg[CELL_NSEGMENT];
+void *alloc_seg[CELL_NSEGMENT];
 pointer cell_seg[CELL_NSEGMENT];
 int     last_cell_seg;

diff --git a/tests/gpgscm/scheme.c b/tests/gpgscm/scheme.c
index 1fc7643..8833950 100644
--- a/tests/gpgscm/scheme.c
+++ b/tests/gpgscm/scheme.c
@@ -602,7 +602,7 @@ static int alloc_cellseg(scheme *sc, int n) {
      pointer newp;
      pointer last;
      pointer p;
-     char *cp;
+     void *cp;
      long i;
      int k;
      int adj=ADJ;
@@ -614,14 +614,14 @@ static int alloc_cellseg(scheme *sc, int n) {
      for (k = 0; k < n; k++) {
          if (sc->last_cell_seg >= CELL_NSEGMENT - 1)
               return k;
-         cp = (char*) sc->malloc(CELL_SEGSIZE * sizeof(struct cell)+adj);
+         cp = sc->malloc(CELL_SEGSIZE * sizeof(struct cell)+adj);
          if (cp == 0)
               return k;
          i = ++sc->last_cell_seg ;
          sc->alloc_seg[i] = cp;
          /* adjust in TYPE_BITS-bit boundary */
          if(((unsigned long)cp)%adj!=0) {
-           cp=(char*)(adj*((unsigned long)cp/adj+1));
+           cp=(void *)(adj*((unsigned long)cp/adj+1));
          }
          /* insert new segment in address order */
          newp=(pointer)cp;
--