Don't cast the return value of malloc/realloc

This patch has been generated by the following Coccinelle semantic
patch:

// Don't cast the return value of malloc/realloc.
//
// Casting the return value of malloc/realloc only stands to hide
// errors.

@@
type T;
expression E1, E2;
@@
- (T)
(
_mesa_align_calloc(E1, E2)
|
_mesa_align_malloc(E1, E2)
|
calloc(E1, E2)
|
malloc(E1)
|
realloc(E1, E2)
)

src/mesa/main/shaderapi.c

@@ -377,7 +377,7 @@ detach_shader(struct gl_context *ctx, GLuint program, GLuint shader)
          _mesa_reference_shader(ctx, &shProg->Shaders[i], NULL);
 
          /* alloc new, smaller array */
-         newList = (struct gl_shader **)
+         newList =
             malloc((n - 1) * sizeof(struct gl_shader *));
          if (!newList) {
             _mesa_error(ctx, GL_OUT_OF_MEMORY, "glDetachShader");
@@ -1299,7 +1299,7 @@ read_shader(const char *fname)
       return NULL;
    }
 
-   buffer = (char *) malloc(max);
+   buffer = malloc(max);
    len = fread(buffer, 1, max, f);
    buffer[len] = 0;
 
@@ -1336,7 +1336,7 @@ _mesa_ShaderSourceARB(GLhandleARB shaderObj, GLsizei count,
     * This array holds offsets of where the appropriate string ends, thus the
     * last element will be set to the total length of the source code.
     */
-   offsets = (GLint *) malloc(count * sizeof(GLint));
+   offsets = malloc(count * sizeof(GLint));
    if (offsets == NULL) {
       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glShaderSourceARB");
       return;
@@ -1363,7 +1363,7 @@ _mesa_ShaderSourceARB(GLhandleARB shaderObj, GLsizei count,
     * valgrind warnings in the parser/grammer code.
     */
    totalLength = offsets[count - 1] + 2;
-   source = (GLcharARB *) malloc(totalLength * sizeof(GLcharARB));
+   source = malloc(totalLength * sizeof(GLcharARB));
    if (source == NULL) {
       free((GLvoid *) offsets);
       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glShaderSourceARB");