[rcore] Calls to GetRandomValue(min, max) will always return min, if not call to InitWindow()

[ChinaBackGo]

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Please, before submitting a new issue verify and check:

• [x ] I tested it on latest raylib version from master branch
• [x ] I checked there is no similar issue already reported
• [x ] I checked the documentation on the wiki
• [x ] My code has no errors or misuse of raylib

Issue description

Multiple calls to GetRandomValue without a call to InitWindow() first will always yield the min value. For example:

GetRandomValue(10, 100);
GetRandomValue(10, 100);
GetRandomValue(10, 100);
GetRandomValue(10, 100);

will always yield 10.

Expected behaviour even without setting the seed would yield a number other than 10.

Environment

Windows 11

Issue Screenshot

Code Example

#include "raylib.h"
#include "raymath.h"


int main() {
    
/*
const int screenWidth = 800;
const int screenHeight = 450;
InitWindow(screenWidth, screenHeight, "raylib [core] - GetRandomValue bug");
*/
    int rand = 0;
    for (int i = 0; i < 10; i++)
    {
        rand = GetRandomValue(10, 100);
        printf("Rand %d\n", rand);
    }

}

[raysan5]

@ChinaBackGo Fixed!