psutils: add safety margin to buffer

The combination of gcc-10.2.1 and musl-1.2.2 detects a possible buffer
overrun psutil.c line 305. Add a safety margin of 24 byts to buffer.

srcpkgs/psutils/patches/buffer-safety.patch

@@ -0,0 +1,20 @@
+--- psutils/psutil.c	2021-02-05 23:12:50.141587998 +0100
++++ psutils/psutil.c	2021-02-05 23:15:17.861925136 +0100
+@@ -38,7 +38,7 @@
+ extern char pagelabel[BUFSIZ];
+ extern int pageno;
+ 
+-static char buffer[BUFSIZ];
++static char buffer[BUFSIZ+24];
+ static long bytes = 0;
+ static off_t pagescmt = 0;
+ static off_t headerpos = 0;
+@@ -97,7 +97,7 @@
+   long r, w ;
+ #endif
+   char *p;
+-  char buffer[BUFSIZ] ;
++  char buffer[BUFSIZ+24] ;
+ #if defined(WINNT)
+   struct _stat fs ;
+ #else