Fix few typos in builtin/ and sotest_main example.

Signed-off-by: Abdelatif Guettouche <abdelatif.guettouche@espressif.com>

builtin/exec_builtin.c

@@ -45,7 +45,7 @@
  * Input Parameter:
  *   filename  - Name of the linked-in binary to be started.
  *   argv      - Argument list
- *   redirfile - If output if redirected, this parameter will be non-NULL
+ *   redirfile - If output is redirected, this parameter will be non-NULL
  *               and will provide the full path to the file.
  *   oflags    - If output is redirected, this parameter will provide the
  *               open flags to use.  This will support file replacement
@@ -53,7 +53,7 @@
  *
  * Returned Value:
  *   This is an end-user function, so it follows the normal convention:
- *   Returns the PID of the exec'ed module.  On failure, it.returns
+ *   Returns the PID of the exec'ed module.  On failure, it returns
  *   -1 (ERROR) and sets errno appropriately.
  *
  ****************************************************************************/

examples/sotest/sotest_main.c

@@ -159,12 +159,10 @@ int main(int argc, FAR char *argv[])
 
 #if CONFIG_MODLIB_MAXDEPEND > 0
   /* Install the first test shared library.  The first shared library only
-   * verifies that symbols exported be one shared library can be used to
+   * verifies that symbols exported by one shared library can be used to
    * resolve undefined symbols in a second shared library.
    */
 
-  /* Install the second test shared library  */
-
   handle1 = dlopen(BINDIR "/modprint", RTLD_NOW | RTLD_LOCAL);
   if (handle1 == NULL)
     {
@@ -261,7 +259,7 @@ int main(int argc, FAR char *argv[])
   ret = dlclose(handle2);
   if (ret < 0)
     {
-      fprintf(stderr, "ERROR: rmmod(handle2) failed: %d\n", ret);
+      fprintf(stderr, "ERROR: dlclose(handle2) failed: %d\n", ret);
       exit(EXIT_FAILURE);
     }
 
@@ -271,7 +269,7 @@ int main(int argc, FAR char *argv[])
   ret = dlclose(handle1);
   if (ret < 0)
     {
-      fprintf(stderr, "ERROR: rmmod(handle1) failed: %d\n", ret);
+      fprintf(stderr, "ERROR: dlclose(handle1) failed: %d\n", ret);
       exit(EXIT_FAILURE);
     }
 #endif