Fix shader type mismatches (#311)

* Update opengl_fragment_shader.frag

* Update opengl_vertex_shader.vert

src/host_shaders/opengl_fragment_shader.frag

@@ -32,7 +32,7 @@ uniform sampler1DArray u_tex_lighting_lut;
 uniform uint u_picaRegs[0x200 - 0x48];
 
 // Helper so that the implementation of u_pica_regs can be changed later
-uint readPicaReg(uint reg_addr) { return u_picaRegs[reg_addr - 0x48]; }
+uint readPicaReg(uint reg_addr) { return u_picaRegs[reg_addr - 0x48u]; }
 
 vec4 tevSources[16];
 vec4 tevNextPreviousBuffer;
@@ -414,4 +414,4 @@ void main() {
 				break;
 		}
 	}
-}
+}

src/host_shaders/opengl_vertex_shader.vert

@@ -27,7 +27,7 @@ uniform uint u_textureEnvColor[6];
 uniform uint u_picaRegs[0x200 - 0x48];
 
 // Helper so that the implementation of u_pica_regs can be changed later
-uint readPicaReg(uint reg_addr) { return u_picaRegs[reg_addr - 0x48]; }
+uint readPicaReg(uint reg_addr) { return u_picaRegs[reg_addr - 0x48u]; }
 
 vec4 abgr8888ToVec4(uint abgr) {
 	const float scale = 1.0 / 255.0;